On AA and SQ I've been able to request and get award space on flights with open J availability. I'm flying SFO/LHR (BA286) in WT+ next Saturday and am trying to UUA to CW but there isn't any award space inventory in any class.

I've got ExpertFlyer alerts running for business award space, but I'm wondering if anybody has successfully requested award space from BA before? From the 3 or so calls I've had with customer support it seems impossible to even find a competent agent who'd understand what I'm asking.

If not — is there any likelihood award space will be opened in the days leading up to/of departure? I've been following the award space calendar in the BA iOS app like a mad man. I'm on a corporate TA booking (Amex) and cannot upfare to business through them due to company policy.