We are booked to go to Barcelona in August and I tried to make a dummy booking to see how busy it is. Our return flight BA407 is only running from August but you can't book it via ba.com or the app if selecting a flight normally. It is bookable via a redemption flight though (which is what we did). I am now worried we are likely to get bumped if BA are not selling seats with only 5 weeks to go.
Is this common do people know and is it worth switching flights now to one that is available via ba.com?

Thanks