VeChain Interstellar launches on September 16: Things to check for VET currency holders before hard

September 16, 2026: Full Guide to VeChainThor Network Upgrade "Interstellar" Hard Fork

On Wednesday, September 16, 2026, the VeChainThor Network will activate a hard fork called "Interstellar". For the holder, the most critical point is that the switching time is not a specific moment, but the height of the block. Activation will occur when the 25,902,540th block occurs, and the exact time to reach that block is determined by the chain itself.

Within a few hours around this time point, any user holding a VET on the exchange will not be able to make deposits and withdrawals. Users running their own nodes must replace software in advance. Users who deposit tokens in self-managed wallets do not need to take any action.

The author of this article did not believe the official announcement, but conducted actual measurements: analyzed the actual block time of the main network in three time periods, as well as the software versions visible to the current public VeChain nodes. The results of both measurements are attached below, including dates, methods and sample sizes.

Interstellar and VIP-255: What is happening to VeChainThor?

"Interstellar" is the name of this upgrade, and "VIP-255" is the improvement proposal number behind it. VIP stands for VeChain Improvement Proposal, which refers to a formal proposal to change the agreement and is voted on by holders of authoritative nodes and economic nodes. According to VeChain, the voting for VIP-255 was held on the VeVote platform from August 10 to 17, 2026, and has been approved.

In essence, Interstellar elevates the VeChainThor virtual machine to the level of Ethereum. The hard fork adopts eleven Ethereum Improvement Proposals (EIPs) from upgrades from Cancun, Prague and Osaka at one time: EIP-1153, EIP-5656, EIP-6780, EIP-7939, EIP-2537, EIP-7951, EIP-7823, EIP-7883, EIP-2935, EIP-7825, and EIP-7934.

A hard fork is a protocol change that is not backward compatible: nodes running old software will regard new blocks as invalid and exit consensus.

The VeChain team clearly pointed out in the official announcement what Interstellar does not involve: there is no token migration, no redemption, no new contract address, the VET supply remains unchanged, the VTHO generation rules remain unchanged, and the pledge rules remain unchanged. The Blob transactions introduced by Ethereum for Rollups are also not included in this upgrade package.

Block height rather than clock time shall govern: Why dates are only approximations

Chain upgrades are bound to block numbers, because the block numbers seen by each node are the same, but clock times may be different. This means that any specific time you read about Interstellar is just a prediction. Its accuracy depends on whether the chain can maintain a stable rhythm.

VeChainThor uses a fixed 10-second slot. If the authoritative node responsible for production does not generate a block in its slot, the slot is empty and the average block-out time will exceed 10 seconds. It is this deviation that determines whether activation will come on time or be delayed by a quarter of an hour or half a day.

According to the node software release instructions, the activation of the testnet occurred in block 25, 891, 380th, approximately September 9. The main network followed up in the 25, 902, 540th block.

Our measurement results: an average of 10.0012 seconds per block in 24 hours

This analysis was completed by the media on September 12, 2026. Method: Get the current block through the common node mainnet.vechain.org and compare it with blocks from previous 8,640, 60,480, and 259,200 locations; the difference between the timestamps gives the average block-out time for each window. A total of 259,200 blocks were inspected for approximately thirty days.

Status at the time of measurement: Block 25,870,700, timestamp is September 12, 2026 UTC 18:54:10. There are still 31,840 blocks left until activation.

• 24 hours: 8,640 blocks took 86,410 seconds, with an average of 10.0012 seconds per block. One slot is empty.
• 7 days: 60,480 blocks took 604,960 seconds, with an average of 10.0026 seconds. There are 16 empty slots, accounting for 0.03%.
• 30 days: 259,200 blocks took 2,592,400 seconds, with an average of 10.0015 seconds. There are 40 empty slots, accounting for 0.02%.

Based on these three rates, the remaining 31,840 blocks are estimated to be activated between 11:21 and 11:22 UTC on September 16, 2026. The announcement time for the VeChain team is UTC 11:15. There is a gap of about six minutes because the announcement assumes that the block time is fixed at 10 seconds, but in fact the average block time of the chain is slightly higher, one to three thousandths higher.

The practical lesson of these numbers is that the rhythm of VeChain remains extremely stable. On a chain where only 40 slots were missing in thirty days, the shift in the activation date four days later is in minutes rather than hours. As a result, you can plan actions for the morning of September 16, but you don't need to schedule a strict window with an accuracy of less than ten minutes.

Note to node operators: Interstellar is not concerned about dates, but software replacements with deadlines

Thor v2.5.0: The node version that supports Interstellar

The reference software for the network is called Thor. The v2.5.0 version released in early September includes the Interstellar rules and two activation levels for the test net and the main net. The release instructions clearly stipulate that operators must update to v2.5.0 before the relevant block height. Configuration files do not need to be changed, and updates are run in-place.

Everyone running their own nodes is affected: authoritative master nodes, public RPC providers, exchanges, custodians, and any company with its own chain connections. Any application running through a third-party RPC endpoint relies on the provider's update discipline.

79% of the visible nodes are ready and 21% are not yet ready

Next is the second measurement we took. The peers endpoint of a public VeChain node displays the software identifier of each peer it is currently connected to. The media queried the endpoint six times at 18:55 UTC on September 12, 2026 at two-second intervals, and de-responded using a peer identifier. The results are as follows: A total of 105 unique counterparts were found.

• 83 nodes Thor v2.5.0 is running, so it is already Interstellar compatible. Accounting for 79.0%.
• 22 nodes are running older versions: 15 in v2.4.4, 3 in v2.4.0, 2 in v2.4.2, and 1 in v2.4.1 and v2.4.3 respectively.

This 21% is not a reason for panic, but it is by no means insignificant. Nodes running v2.4.x will reject blocks generated after the fork and stay in the old state. If your wallet or portfolio tracker happens to be connected to such an endpoint, you'll notice that balances and transactions seem to freeze there, even though everything else on the chain continues.

What this measurement fails to show is part of the picture. This is just a single public node's perspective on its direct peers and therefore does not represent the complete picture of the entire network. It is impossible to know whether the authoritative master node of the actual production block has been updated, because the peer list only names the version and does not indicate the role. The extremely low empty slot rate indicates that block production is running stably; however, this is not evidence of the producer's software version.

Binance suspends VET deposits and withdrawals: Window period on September 16

Exchanges usually follow standard procedures during hard forks: stop deposits and withdrawals before activation, update nodes, wait for a few confirmations, and then reopen. Binan announced on September 11 that it would suspend deposits and withdrawals of VET at 19:15 on September 16, Korean time (10:15 UTC). According to the announcement, transactions will continue during the suspension period; once the network is stable, deposits and withdrawals will be open again.

This has three practical consequences. First, if you want to transfer VET from the exchange to your wallet before fork, please schedule it to be completed before 10:00 UTC on September 15 or September 16. Second, suspension of transfers does not mean suspension of transactions; your positions can still be sold. Third, the "post-stabilization" reopening is a soft deadline with no specific time limit and may sometimes take half a day.

Other trading platforms will announce such suspensions individually, usually in their announcement or status areas. The key question you need to solve yourself is: Has your provider issued any notices? See our guide for how to access reliable information pages. If you want to also check the transparency of your trading platform's overall operations, regulated addresses can be found in cryptocurrency exchange comparisons.

The transfer window closes a few hours before activation and there is no fixed time to reopen

VET in a self-managed wallet: Why no action is needed

For self-managed users, Interstellar is a non-event. The official announcement made it clear that ordinary VET and VTHO holders do not need to take any action: the address is still valid, the private key is still valid, and the position will not change. Anything you have in your hardware or software wallet will remain the same after that.

Still, there is a qualification that involves displaying rather than holding positions. Wallet applications communicate with the chain through nodes run or purchased by the manufacturer. If your application connects to a node that is still running v2.4.x after fork, it will display outdated data. The solution is simple: wait a few hours, update the application, and switch nodes in settings if necessary.

Anyone who still keeps tokens on the exchange and takes this opportunity to consider moving to self-custody should calmly examine the device and its differences. A hard fork is a great reminder because it makes you aware of what your current access depends on.

Eleven EIPs: What developers can use from September 16

The core technology of VIP-255 is the alignment of VeChainThor VM with Ethereum. Can be divided into two groups.

New opcode for contracts

EIP-1153 introduces transient storage, which is storage that exists only for the duration of a transaction and expires later. This makes reentry locks and similar models much cheaper. EIP-5656 adds the MCOPY instruction to quickly copy memory areas, EIP-6780 limits the behavior of SELFDESTRICT, and EIP-7939 adds an instruction to calculate leading zeroes.

Chain verifiable cryptography

EIP-2537 brings arithmetic operations on the BLS12-381 curve, and EIP-7951 brings signature verification on the secp 256r1 curve. The second curve is the curve built into smartphones, security chips and access keys. For VeChain, this means that signatures generated by mobile phone security chips can be verified directly on the chain without having to go through expensive contract detours. EIP-2935 makes historical block hashes available through system contracts, and EIP-7823 and EIP-7883 adjust modular exponentiation and its cost.

Gas limits and block sizes: Two new caps

Two things in the package affect capacity rather than cryptography. EIP-7825 sets a fixed Gas cap for a single transaction, specifically 16,777,216 Gas. EIP-7934 limits the block size of encoded forms to 8 MiB.

These two limitations are designed to improve robustness: a single huge transaction can no longer fill a block alone, and oversized blocks can no longer be transmitted slowly across the network. This becomes relevant for developers deploying very large contracts at once or packaging bulk operations into a single transaction. Anyone running such a process should test on the testnet by September 16, and Interstellar has been in effect on the testnet since September 9.

Possible problems in hard forks and how to detect

The most common interruption is not chain splits, but displays gaps. Typical symptoms during activation: Withdrawal remains in the "processing" state for longer than usual. The status displayed by the Explorer is different from that of your wallet. Decentralized applications report errors when sending.

In all three cases, waiting is the correct initial response. What you should avoid is what fraudsters exploit in every upgrade: messages that lead you to "migration" or "wallet verification." Interstellar does not involve migration. Any prompt that requires you to enter your mnemonic or send a token to an address for "conversion" is an attempt at theft.

The second habit worth cultivating is: Don't just check deadlines when they appear in the news, check them together. Browsing the current market deadline once a month means that there will be fewer cases of encountering expired deadlines.

Activation schedule

In order that affects you:

• Before September 15: Node operators swap their software with Thor v2.5.0. Developers conduct tests against the testnet.
• September 16, starting from about 10:15 UTC: Binance will stop VET deposits and withdrawals. Other trading platforms set their own windows.
• September 16, approximately 11:20 UTC: Block 25,902,540th fell and Interstellar went online. Based on our measurements, this is six to seven minutes behind the announcement time.
• After: Exchanges reopen transfers at an uncertain time, as long as their nodes keep up steadily.

Check VeChain Interstellar: Summary of Points

Transfer money in advance. If you want to transfer VET before fork, please complete it before the morning of September 16. Which trading platforms clearly announce that such windows can be found in the comparison of cryptocurrency exchanges.

Determine what applies to your situation. Owning a node means having an obligation to update to Thor v2.5.0; owning a wallet means no action is required. Anyone who wants to completely resolve the difference between exchange balances and self-custody can find the relevant device in the hardware wallet comparison.

Keep calm and collect dates. Display errors after fork usually resolve themselves; real deadlines do not. Anyone who gathers positions and deadlines in one place can find the right tool in the analysis platform comparison.

List of sources: VeChain official announcements on Interstellar and VIP-255, and Thor v2.5.0 release notes, which contain two activation heights. Block time and version data are from our own survey conducted on September 12, 2026.

(As of September 12, 2026. This article does not constitute investment advice. Price and fee structures are subject to change; please check terms with your provider before purchasing.)