They’d have been in complete and utter bother from the start.
Manchester - routed by the gangs who’d not welcome the appearance of new rivals, and who’d find the captured armour handy for inter-gang disputes afterwards.
Liverpool - routed by the gangs who’d not welcome the appearance of new rivals, and who’d nick what was left of their logs
Birmingham - fighting a jihad in and around Sparkbrook which’d make the Taleban look like Buddhists; a brutal urban fight in and around Aston where the local drug gangs would significantly overmatch the average BTG’s firepower, and as for Walsall and the surrounding areas, may the Lord have mercy upon their souls (particularly in the vicinity of Bloxwich)
As for Scotland - “ Sometime about the year AD2022, the Ninth BTG, which was stationed at Eburacum, where York now stands, marched north to deal with a rising amongst the Caledonian tribes and was never heard of again….”