In response to the question "What will happen to the parachain after the block space (Coretime) is online?" Bastian Köcher, Polkadot core developer and Polkadot Fellowship member, said: "Coretime will be online in the future. No matter what developers build now, almost You can be sure that the parachain will continue to run. For example, if you build a parachain now, it may need to make some changes or a runtime upgrade, but it should be compatible with Coretime, and there will be no situation where the parachain will not be able to run by then. I've heard some concerns before, and now might be a good time to clarify that this isn't going to happen. Whatever you build now will continue to work, or there will be some less complicated upgrade path. "
Regarding Polkadot’s important future plans, Bastian Köcher said: “We delivered what was mentioned in the white paper, the only thing missing now is the bridge, or the bridge between Kusama and Polkadot. We also want multiple Polkadot implementations , such as Kagome (Polkadot’s Go implementation, still under development), their progress is actually amazing, they can already verify the parachain.”
Regarding the development progress of the bridge, he said: "To start the bridge, we are still waiting for the completion of Beefy. Beefy (the bridge protocol) is roughly planned to be online before the end of the year. After Beefy is online, the bridge will be ready." ( PolkaWorld)