If you cancelled first, you won't get the redeposit fee refunded, hence the advice in the main Rebook thread to leave it as long as you can, given than BA tends to cancel services 2 weeks from departure. If BA had cancelled first then not only would you have the full refund option but a range of other options open to you in terms of rebooking or rerouting.

It's normal for the cancelled sector to linger in MMB and the App, in fact they sometimes appear to move the flight to a random date 3 months down the line, if you cancel close to departure. The reason for this is that it is much easier for the back office team to locate your booking and the relevant details if the PNR is still in the GDS system. The refunds team is somewhat overwhelmed by all accounts, so it may take some time to see the cash back, particularly if you paid in CAD.