Alternatively, contact K2 and have a proper conversation with them about the issue in hand.

BA have changed from Antler to K2 - that happened some point last year. I've had more than one bag issue and have had need to contact both at various points; when Antler supplied a far too large bag than the one needed, I simply called them and had a good conversation about the issue at hand, and they simply dispatched a new bag and their courier picked up the wrong bag. Issue solved - no drama, no "oh it isn't Antler I bought my plane ticket from".

Never underestimate the value of a good call - try K2 and explain your issue.

(And for the record - the K2 bag I have is actually quite good).