I would recommend strongly against checking a bag for a BA connection at LHR. We've had two miserable experiences in a row. Last time (March 10) BA lost our bags for 5 days and fatally damaged one of them (a relatively expensive Rimowa). Our connection was nearly 4 hours, so there was really no excuse for our bags not making the onward flight. BA cs was absolutely worthless, and lied to me repeatedly. Absent an unusually pro-active Iberia employee at BCN, I don't think we ever would have gotten our bags.