It’s from wiki so you probably won’t believe it, but here goes.
“The trimmable horizontal stabilizer (THS) moved from 3 to 13 degrees nose-up in about 1 minute, and remained in that latter position until the end of the flight.”
Black box and cockpit recorder, according to the Popular Mechanics story mind you, tell a different tale. That’s all I can tell you.
In about 1 minute, eh? Sounds like the pilot in control trimmed it that way to “help” him hold it in a full stall all the way to ocean surface impact!!
JC