The warning light came on during three previous flights: on Dec. 7, Jan. 3 and Jan. 4 — the day before the door plug broke off. Homendy said she didn’t have all the details regarding the Dec. 7 incident but specified the light came on during a flight on Jan. 3 and on Jan. 4 after the plane had landed.
So December 7th. The day the aircraft leaves the MRO AAR after its WiFi install. (cannot post flightaware image, new user)
AAR says they dont touch plug doors. However satellite image shows some kind of ramp near the location of that door on some variant of the 737 unable to see if it is a MAX 9. Look for AAR in Oklahoma on Google maps (i am not allowed to post the image because I am a new user).
I think the NTSB should look into this despite the claims of the MRO.
Especially if the forensics find markings on the bolt holes and where the door rests indicating that there was a bolt there at some point. If not then I guess the most likely scenario is still them being missing from the get go.
You can watch a WiFi retrofit video on youtube by United (for A320) but you can still see that it appears to be a massive job.