Ref the chairs I do use them when I feed them at the same time so mid afternoon and bedtime is that still going to be ok?
Yes, for sure. Just as long as they're not going to sleep in them, that's the only thing I wouldn't use them for.
If the nap in the cot just doesn't happen so say I've tried for 45 mins do I try again 2 hours later? Not sure about this bit as ill need to watch over the other one ad my mum will only stay for the initial nap time?
I would try again in 1hr or so. So, get them up (or just the one if the other is sleeping) and have a bit of low key A time and feed him a little more if needed. Things could get a bit off for a few days with both of them, but it should come right pretty quick once they're going down on their own for naps.
Also if the nap lasts 45 mins or so but no longer do I just allow a longer catnap to make up?
Yeah, bring it earlier and let it go a little longer, but not so long as to cause issues with BT.
Good news is S has just gone to sleep in 15 mins and I'm almost by the door at last Yey !
Great! Well done S and you!!