will MoD staff based in Scotland follow Scottish tax rules or the UK govt rules?
Live in Scotland now you have an "S" at the the start of your tax code, specifically for the purposes of identifying you as a Scottish tax payer, subject to Scottish rules. IDK if service folk have this or not (suggest one will be along shortly to tell us), But I got one, and I'm planning on moving my tax domicile daaaawnnn saaafff in a few weeks, so I'll let you know how that goes.