@LostFrog thanks for the reply.
He's not waking for the toilet, it's definitely company that he's after. My tactic had been plonking him outside so that he hopefully learnt that if I'm coming downstairs in the night the only thing that happens is the toilet. No games, no fuss, no conversation, no cuddles. He went because he could, not because he needed to, if that makes sense.
Set up is a crate, but when him being unsettled started we left the crate door unlatched so that he can get into the attached pen. Our house is very open plan and from day 1 he's been in the crate in the living room, so the idea behind the pen was to give him a bit of additional freedom while also preventing him getting to things he shouldn't!
Last night he was settled in his favourite spot on the floor so we decided to risk it and leave him there while we went to bed. He stayed downstairs for long enough for us both to get ready for and into bed, and then he was up in our room, settled in the corner and asleep before I was!
He barely moves and we don't know he's there so the temptation is there to just let that be where he sleeps for an easy life, but out bedroom is also the only room that is truly ours, our sanctuary I guess, and I'm keen to keep it that way. Stupid perhaps bit hey ho!
@Handsfullofholes 2 presents for ours (plus a new harness on order - that's a necessity, though
). I know that DM, DF, MIL&FIL, BIL&SIL, have all also bought for him. 