BA flights generally credit at the same values as QR flights for the same distance / fare class (and bear in mind that BA does not have a Lite P business fare class, so you wont have to worry about those lower values). Perhaps you had previously seen the return values on the QCalculator and didn’t realise you had to select one-way?

In my experience, all oneworld (including QR) flights credit to QRPC according to the marketing carrier (eg QR operated flights sold by BA would credit as BA flights) and without QRPC status bonus Avios.