According to PANews, OP_CAT, also known as BIP-420, has been launched on Bitcoin's official testnet 'SIGNET'. This will allow developers to build advanced OP_CAT applications using CatVM and conduct real-time testing on the official test network.
Previously, 'signet' was the name of the Bitcoin test network, designed specifically for developers to test their software. There are no miners on 'signet', with 'signet' operators creating a block every 10 minutes on average, without the need for proof of work. For those familiar with the Ethereum test network, Bitcoin's 'signet' is similar to Ethereum's 'sepolia' network.