Deja Dup could maybe be smarter in the specific case of SMB mounts and only try to mount the root folder...
If you switch your settings from:
Network Location: smb://1.2.3.4/backup/UbuntuBackup Folder: MyMachineBackup
to:
Network Location: smb://1.2.3.4/backup Folder: UbuntuBackup/MyMachineBackup
do things work like you expect?
Deja Dup could maybe be smarter in the specific case of SMB mounts and only try to mount the root folder...
If you switch your settings from:
Network Location: smb://1. 2.3.4/backup/ UbuntuBackup
Folder: MyMachineBackup
to:
Network Location: smb://1. 2.3.4/backup MyMachineBackup
Folder: UbuntuBackup/
do things work like you expect?