Yeah you will almost certainly need to download the chain from scratch. If you want to attempt this you would need to stop lightning during the process. Remove knots, install core and then let it sync. Once it’s fully synced you can start LN again. Might be worth checking with Start9 team if there is a way to do this since you may even have trouble removing knots without removing LN since it’s technically a dependency. Hard to say for sure without giving it a try.
Discussion
Thanks nostr:npub1q8gth72n0mcl6rwls905rsvfvuu0dgaq7cq028rc9d7c3ygnp4xq84awvk just sent them an email.
When you say, stop lighting, are saying to close all channels, or just stop transactions?
You would not need to close your channels, but LND would be unable to operate until you have resynced Bitcoin Core.
You should be able to ‘stop’ the lightning app in the Start9 interface so it’s shut down during the process. Then once you have a new version of Bitcoin running and fully synced you should be able to start it up again. You just don’t want it running during the migration and probably won’t be able to uninstall or upgrade bitcoind while it’s active.
Perfect thanks F. Appreciate your help brother