I upgrade as soon as new versions come out, I like living on the edge :) if something goes wrong, there are backups.
As for musl, I haven't mentioned it since OP wants to run containers - and in that case, musl doesn't matter. And for running programs natively, many are available as packages (with any musl incompatibilities already resolved). But yeah, if you venture outside these limits, you can definitely run into issues with musl.