Baby rolling over at night -how to transition swaddle ?

A

Ok, ladies ! I am a first time mom so I basically know nothing and I need some help. My baby is 4 months old and for the first time last night he rolled over in his pack n play. Thankfully he started whining because he couldn’t get himself back over and that woke me up. He holds his head up and everything, but it just scared me and he ended up doing it again. Needless to say, I didn’t sleep because i was afraid that he would keep doing it . We have him in the Love to Dream swaddle. Since he is now rolling over , it’s time for us to transition. My questions are :

1. How long do you leave one arm out before you take the other one out? After that , how long before you remove the swaddle completely ?

2. do I just let him stay on his belly and sleep when he’s rolled over ? I noticed that his nose and mouth were against the pack n play mattress some and that’s what worried me . I was afraid that he couldn’t breathe .

Any other advice is appreciated! Like I mentioned , I’m a first time mom and this is all new to me !