Neo has announced the closing date for the T4 TestNet. The network will be shut down on August 31 at 8:00 a.m. (UTC), leaving the T5 version as the sole official N3 TestNet.
The T5 network was launched in April alongside NeoCLI v3.2.1 in order to support breaking changes to the protocol, namely native contract modifications that would invalidate past state on the T4 TestNet.
T4 continued operation in parallel with the T5 network in order to support hackathon participants and other developers who had already deployed applications to the network. Now that the T4 TestNet is closing, smart contracts will need to be redeployed to the new network.
Since the T5 TestNet launched, Neo has received numerous updates. The NeoCLI v3.3, 3.3.1, and 3.4 releases introduced new changes which developers will be able to take advantage of on the T5 TestNet. Examples include the Murmur32 hash function, a max block size increase, the MODMUL and MODPOW opcodes, snapshot isolation for contract invocations, and more.
Both the Neo N3 MainNet and the T5 TestNet currently operate on NeoCLI v3.4 nodes or their NeoGo counterparts running v0.99.2. Developers can acquire NEO and GAS assets via the new faucet introduced for T5, available here.
The original announcement can be read at the link below: