Launchpad builds for i386 fail: Command errors (if any): b''

Since some days ago, the nextcloud snap, based on core18, is failing to build for i386 on launchapd.

This is what the log shows:

...
Restarting host AppArmor
Command output: b''
Command errors (if any): b''
2025-12-11T01:02:57Z INFO Waiting for automatic snapd restart...
snapd 2.60.4 from Canonical** installed
snap "snapd" has no updates available
error: cannot perform the following tasks:
- Ensure prerequisites for "snapcraft" are available (cannot install snap base "core18": snap "core18" assumes unsupported features: snapd2.61 (try to refresh snapd))
Install failed
...

We have configured the following source snap channels for automatic builds:

snapcraft	7.x/stable
snapd		latest/stable

Thanks for any help!