Well what she did was use the forward facing belt path, as I told her, with the seatbelt, which was fine. BUT she decided to continue to use the rear facing belt path with latch,too. More is safer, right?
She told me she used the ff belt path, but when she brought in the seat, the latch strap was in the rf path, which was my tip off to ask a question. She brought it in so we could remove the harness covers we were using to keep Matt from pushing the chest clip down and taking his arms out, and also she hadn't put the harness at or above for ff. He needed the first unslanted slot.
Oh, she did take off the recline boot. I DID tell her to do the other stuff, but the safe stop is missing, of course. She may not totally be to blame for that. Maybe I took it off so it wouldn't get lost and put it somewhere. Maybe it's where the latch strap I took off the Avenue and put in a safe place is.