I have got used to my little cat door now, and am quite happy to come and go. Mum went off to her nightshift last night at 11:30pm and left me sleeping on her bed. When she got home just after 7am I got up and joined her while she had a snack. It always helps her to have some toast before she pops into bed, so that the rumbly tummy doesn't wake her up at midday.
The cat door is a little higher than my last one, and at our old place my mum had a stool outside to help me climb in. I am managing quite well here, and mum figures it is like a bit of a core exercise for me to have to stretch a little bit. Usually while she is home and the weather is mild the back door is open, so that I can come and go through there.