Welcome to the forum. Xplorer has good advice. One option is to drive to the end of the walk and get a taxi to the start, cost around $100. The advantage of this is that you can end the walk and just drive away. See
https://www.mtbeauty.com/transport/moun ... i-service/mtbeautytaxi@gmail.comThe driver I used was Roly, lovely bloke.
The only place where you may come unstuck is at Ropers Hut. Just before the hut the 4WD track goes left and the AAWT goes right, a bit hard to spot. From the hut go out the door to the toilet and the AAWT is a few metres past that, snow poles.
There's good water everywhere, and plenty of campsites. After The Park there's a few hours of exposed walking, should be okay. Big River will be about knee deep, so find a solid stick and take it slow. The chain may be in place; it often comes away in winter. The Big River campsite is small, limited toilet areas. I always find that while going up T Spur is tiring it's a lot easier on the knees than descending Duane Spur.
There's a nice sheltered campsite at the top of T Spur, good water. You can camp in Camp Valley at the Howmans Falls turnoff, but it may be cold. There are spots on the north bank about 150 metres distance up the hill. Cleve Cole has a big clearing, sheltered. If the weather is bad on the last day you can go down the Eskdale Spur, steep at the top. When you get to the road you can go down the road (longer, gentler) or the foot track (shorter, steeper). Staircase is a bit rough on the knees.
Just pace yourself, take your time, have options planned and you'll be fine.