Can TA transfer booking control to BA?
 

I've got a TA booking through Amex Global Business Travel on BA metal, on which I'm trying to upgrade from WT+ to CW. The flights have availability but because the TA has ownership of the ticket, BA can't touch it until OLCI.

Is the TA able to release control of the booking to BA before T-24? Or is the only way to wait until T-24? Thank you all!

Unfortunately no. The booking only passes to BA after the first sector is flown. If it is a BT or IT fare then the ownership remains with the TA. What type of upgrade are you trying to get? If it is a published fare, then it can be upgraded with Avios and that is when BA can take ownership. If it is a paid upgrade, you have to do it through TA. If there are non-BA sectors on the ticket then it's not eligible for UUA and the same applies if it is a BT/IT fare.

Cool, thank you for the info. UUA isn't available (no U inventory) so looking to see if I can make myself eligible for a POUG pre-OLCI. Both sectors (SFO/LHR, LHR/SFO) are BA tickets on BA metal. So will wait till T-24/airport and see what my options are then.

I have been able to upgrade a TA booking using Avois several times prior to travel. Just call up the BAEC and tell them you have a TA booking that you would like to upgrade using Avios (if you have confirmed there is availability). Once the upgrade happens, the ticket transfers to BA and the TA can't then touch it, so if you need to make any subsequent changes, the TA will not be able to do it.

I have also done this with a TA booking....however OP isn't looking to upgrade with Avios as there is no availability