Ok so an update, we went for a walk this afternoon and he napped (which he NEVER does in the stroller) for about an hr from 2.45pm to 3.45pm, woke up mega grumpy. BT at 7pm, started crying whenever I put him in sleeping bag so had a little bit of play (5 mins) to change his mindset then put him to bed slightly whingy. Quiet as soon as I left the room, had a little chat to himself then asleep. Where do I go from here. He clearly needs some day sleep as its very unusual for him to fall asleep in the stroller (but we go for a walk each day at a similar time and this is the first time he's napped). Is this likely to be a regression, routine issue, teeth, or nap drop??or is it a case of only time will tell??