Community mailing list archives
Migrating with OpenUpgradelibby
DevCO Colombia , David Arnold
If you are concerned with migrating your own modules from one version to another, I would like to recommend you to have a look at OpenUpgradelib.
As per it's contributing and social stats on github it can probably still be considered as a very little known treasure. Or else, as a corollary, very few people are concerned with updating modules, which seems hard to believe.
You can find it: https://github.com/OCA/openupgradelib