• Working on an app using CloudronVersions to publish, suddenly the app would not update in the Cloudron dashboard.
• CloudronVersions.json is ~1600 lines long, from 0.0.1 to 0.7.5, jumping a few so about 60 versions
• on last update CloudronVersions.json "lost" versions 0.7.2, 0.7.3 and 0.7.4 (and who knows what from earlier in the chain), so app running last version 0.7.4 would not find/recognise 0.7.5 as an upgrade
• fixed by deleting versions 0.0.1 through 0.7.0 to shrink the file, copying 0.7.1 to 0.7.4 and manually editing values
• app then says 'oooo, I see I am on 0.7.4 and found 0.7.4', and allows me to upgrade to latest 0.7.5
• my build cycle is automated, I never touch CloudronVersions.json

Maybe lazy layman's diagnosis : some CLI bug in cloudron versions add loses content in Versions while adding a new one. Triggered by length limit or buffer constraint ?

Not a problem as such, as I now know how to fix it.
Surfacing this in case others come across it, maybe Cloudron team can check it when no other pressing tasks.