Is Sony Backup&Restore firmware dependent?

I sent my xperia z2 to repair one month ago and am expecting to get it in a few days. I've backed up my important sys and app data to SDcard with sony backup&restore app(lollipop 5.0.2) and i want to restore them after a clean 5.1.1 install... upgrading to 5.1.1 after restore is an option but then it wont be a clean install of 5.1.1. maybe i should restore and back up again with 5.1.1 but i dont know :)

Has anyone tried this? is the backup app of Sony firmware dependent?