6.8.2 went out, and it carries florent's proxy patch, so the thing that was stopping you switching channels has cleared.
Before you do, though, the 6.8.2 changelog lists exactly one bug fix, the fetch failed proxy one, with xo-server at 5.208.3 and the proxy at 0.31.10, and there's nothing in it about metadata backups or BodyTimeoutError.
Your own post above points the same way, since you're seeing the stall on sources at the latest commit, and that commit already has the proxy fix in it. So I'd treat the metadata timeout as a separate bug that 6.8.2 won't touch, and I couldn't find an open issue covering it, though I might well have searched the wrong words.
Might be worth a mention to @Team-XO-Backend, mostly so the metadata half doesn't quietly get filed as fixed by 6.8.2.