How do you collect him? Mine will sleep in the car if really tired, in fact I avoid a late car journey for this very reason. (Alex has Discos in her cot at bedtime if she isn't tired enough!)
I would either try to give a very short catnap earlier than 10.30 for about 30mins or, if the nap is longer than 30mins, then a very short nap of 30 mins around 3-4pm, just to top up and relieve the overtiredness. If you can get throught the overtiredness then hopefully the early wakings would get sorted, then if you can encourage a wakeup of 7amish, you can hopefully give him a nap around 12ish for a couple of hours, enough to see him through 'til bedtime.