Hi! I am planing to book a trip from São Paulo to barcelona , I choose the sky scanner to help me. The site finds a good ticket on chepOair.com, the problem is that there is a connection of 90 minutes in London - LHR. Is that enough time? And if I loose de connection to barcelona the company (TAM - GRU TO LHR // AND BA LHR TO BCN BOTH MEMBERS OF ONE WORLD) give me another ticket for free?