Liam Lawson had the opportunity to drive the Red Bull RB20 at Silverstone on Thursday. While it was technically a filming day, the timing was significant amid the uncertainty around Sergio Perez. Lawson is a contender to replace Perez if he loses his Red Bull seat midway through the season. That could happen if he’s more than 100 points behind Max Verstappen after the Belgian GP, activating a break clause in his contract. Despite winning seven Grands Prix with the Bulls between 2014 and 2018, Daniel Ricciardo isn’t thought to be in the running. His form at junior team RB has simply been too in…