Comment 3 for bug 1960089

This would be a rather trivial fix. In d-i/source/partman-auto/recipes-amd64-efi/atomic one only needs to change this stanza:

512 1024 768 ext4
 $defaultignore{ }
 $lvmignore{ }
 method{ format }
 format{ }
 use_filesystem{ }
 filesystem{ ext4 }
 mountpoint{ /boot } .

Simply doubling the size allocation would be easy, as storage is cheap these days:

1024 2048 1536

I'll submit a patch soon with this fix.