Stomach sleeper

Sooo for the past 2 months we have been going through hell with my LO sleep habits. For about 6 weeks he wouldn’t sleep except on my chest. He would wake up about every 40 mins an cry until I nursed him back to sleep. We finally hired a sleep consultant to help us because we had no other options. Well my now 4 month old is sleeping in his own crib (he out grew the bassinet)

Last night instead of putting him on his back we put him on his stomach we thought he might be gassy. Well within 30 seconds he was asleep. I thought he has his owlet and we have the video monitor on him. I’ll keep checking on him throughout the night. Well I did just that and he slept from 7:30p to 7am.

Now my only concern is he hasn’t fully rolled over yet but he can lift his chest

off the ground and can move his head from side to side (he has been doing that for 2 months already)

Do any of your mamas let your baby stomach sleep? I obviously understand what they say about back sleeping.

Thank you