Update.
1 week out from leaving on our trip (we were able to move the trip forward) took out the camper for 3 nights to test out in different weather, to test out the annexe and het the kids prepared. We did different places each night to get used to set up/pack away each day as occassionally we may need to do this. On the way back somdone pulled out into us. Missed the car luckily but got the trailer. The wheel was all bent and angled back so possibly some damage to the axle. Broje off a bit of the water tank, the gas bottle is scratched up (luckily didn't blow!) The wheel guard is all bent and twisted up. Had to wait around for a tow and then do trips from the repairers (40km away) to get our stuff out.
I explained about our trip and circumstances and bookings like the spirit of tas in approx 8 weeks and it's looking like it's not going to happen before then. Apparently it's quite a process and lots of messing around back and forth between the repairer and the insurance company
We now have to either stay put ( and cancel all of our bookings and lose out on deposits, plus we had organised distance ed and they cancel it if you don't leave within a certain timeframe) or we could take the car and tent and take off for the start of the trip and loop back to pick up the trailer when it's ready. Feeling pretty devastated so just trying to stay possitive and hoping to get good news from the assessment. Perhaps it won't need much work at all.