Another update
Just heard back from BA customer service after I requested a status. Essentially they said sorry for the inconvenience etc etc and here is a voucher which can be used for future travel . Thanks for the voucher but no further light was shed by them on what had occurred and I'm presuming they don't intend to for whatever reason.
Dont see the point of pursuing this with them any further. Lets see what happens next time in T5, one would hope for a better experience but I'm not holding my breath.