Invalid signature key

Since the pmaports split (although I don't think it has anything to do with it), I'm unable to use pmbootstrap due to getting an "Invalid signature key". The full error is the following:

▶ pmbootstrap build --force --strict zpui
[19:17:27] Cleared up ~0 MB of space
[19:17:29] ERROR: Invalid signature key: alpine-devel@lists.alpinelinux.org-5261cecb.rsa.pub
[19:17:29] See also: <https://postmarketos.org/troubleshooting>
Run 'pmbootstrap log' for details.

This happens with any package I'm trying to build or any device image I'm trying to make, basically any action for which the Alpine repos are required. I can't even enter an already existing chroot.

I already tried removing just the offending key, and then even wiping ~/.local/var/pmbootstrap completely, but no dice.