No new problems here really, but we haven't discussed it:
As soon as we add system_update_8100(), it will be impossible to run sites on 8.1.x, because if we add system_update_8030() to both 8.0.x and 8.1.x afterwards, then that will not run (schema version is higher).
While 8.1.x is currently dev only, then we can just say that running it isn't supported.
However, once we get to beta/rc, I'd expect people to start running it - especially for new site development where that site is going to launch after April 20th.
Options:
1. Ignore this completely, possibly keep head2head going.
2. Ignore this until beta or release candidate, then try to make any new updates to the 8.0.x branch also run on 8.1.x (by having two 8.1.x updates and checking state etc.)
3. Ignore this until beta or release candidate, then just try not to commit any hook_update_N() to 8.0.x at all from then onwards.
4. Work on a replacement update system that doesn't rely on sequential function numbering (but still supports dependencies), then use that for all 8.1.x updates
Closed: duplicate
9.5
Last updated
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
Marking this duplicate of #3108658: [policy] Handling update path divergence between 9.5.x and 10.1.x → which describes a similar problem for all minor releases.