Did you book with Iberia or with BA? First of all you have to call whoever issued the ticket.

Iberia's first instinct will indeed be to put you on a later MAD-BIO so it pays to be proactive and call them and try to get the GLA-LHR-MAD pushed forward. Look up what your preferred flights would be (on BA and IB) and tell them that's what you prefer.

You can also take another look at current prices for your dates. You should be able to demand a refund from Iberia for the schedule change. You might find a more convenient route or cheaper fares. Unless mileage/TP running that seems like a horribly inefficient routing.