Q: Core v30 compatability and importing into electrum

Hello, I was testing Jam on Umbrel:
- I was running a sweep with three destinations outside Jam
- Bitcoin Node has updated to Core 30.0 (damn the auto-update!), so opening Jam the alert above appeared;
- since then, differently from your tutorial, my system crashed. Neither Node or Jam was working. No way to restart them: Node stuck so Jam impossible to open.
- I immediately backed up both Bitcoin and Jam directories in located in ~/umbrel/app-data/
- wanted to reinstall apps, so uninstalled both by web interface (impossible to uninstall Bitcoin Node with Jam in the system)
- so reinstalled Node, restored app data and it started well, fast recovering sync
- then reinstalled Jam, restored app data with rsync -avh --progress --delete /data/backup_umbrel/jam/ ~/umbrel/app-data/jam/
- Jam restarted well, with the default wallet, recognizing the password, a little stuck for a moment in "Unlocking", then opened but... NO FUNDS
- the passphrase is correct
- so I imported it in Electrum, where I can see all the transactions and some funds, but only few (1/10 of the original ones)
I understand probably made a homemade wrong fixing (and probably I'll pay for it), but I hope in some help, especially considering the discrepancy between Jam and Electrum with the same seed.
Thank you in advance