Good analysis justme69. I agree with you that if the FDR signal was received at rotation the L gnd control relay CB was in. R2-5 is in air mode when not energized so a failure of the relay would put it in air mode. One of the contacts goes to the position lights, obviously strobes in both position. If the strobes were on on the ground, not anticollision light, R2-5 wasn't energized. Also I had a nose oleo strut overinflated one night and along with strobe lights on the ground I could not reduce power on taxi below flight idle. I am sure they would have noticed that on taxi out. Another relay controls flight idle off the same circuit breaker.