Grobag to duvet help??!

[mamababa]

DS is 23 months and sleeps in a sleeping bag. He moves around the cot a lot in the night. Is it good to get him used to a quilt before he goes to big bed? Tried him last night and he woke up every 2 hours ish. Am also worried he'll climb out of the cot (he can get his leg on the top) Should I just wait until he goes into bed in the spring (when hopefully its a bit warmer) and do it all then ??

We did it the other way around: moved DSs1 and 2 into their big (normal sized single) bed still in their grobags with cotsides at the bed. After a few? couple? of weeks (I cannot remember how long) they got duvets with exciting new bedcovers with the cotsides still in place. This prevented quite a lot of waking up due to being cold, but not all .
They got the hang of it fairly quickly.
DS1 was just under 3 and DS2 was 2 but had to do as his big brother did...