You may struggle during groundschool where you should be aiming for at least 3 hours work a night and at the weekend you will be going back through that weeks work and potentially brushing up on the older stuff. Added to this is the - now compulsory - foundation degree in Air Transport Management which can only add to your workload.
For a more definitive answer you will probably be better off phoning OAT and talking to one of the training advisers.
HTH
Phil.