Don't over think this. You have two days dedicated to stretching, lifting, and conditioning. If you want to add more conditioning via the airdyne I'd keep the airdyne on the stretching days to keep the two days of lifting dedicated to lifting and nothing else. You can put them on the lifting days as well, it's just up to you, your body, and how your schedule dictates it. It's not life or death.
LOWER YOUR TM 85%
Original 5/3/1 or 3/5/1 or 5's pro ( Pick one and get to work)
FSL 3-5X5 (Start with 3x5 and go from there)
Assitance ( Keep it minimal )
The strength aspect is now a "train to maintain attitude" as your main focus/goal is conditioning.
Dont expect to hit huge PR's