Parking with caravan at Dover Ferry

Jim and Isa

We are travelling to France for the October half term holiday. Our ferry leaves at 0420hrs. Does anyone know if it is possible to park at the ferry terminal a few hours before the crossing ( say from 9 or 10pm) with the car  and caravan. we usually use the
tunnel but got a really good deal on ferry so thought we would give it a go.

Any other suitable advice would be appreciated.