Not sure if this post will be considered helpful or not... but here goes....
Tenterfield - Texas (116km)
Texas - Narrabri (273km)
Narrabri - Gilgandra (215km)
Tenterfield - Goondiwindi (via Texas) - 230km
Goondiwindi - Narrabri (224km)
A little googling suggests:
Tenterfield - BP (open to 9:45pm except weekends which are 8pm), United (open to 10pm), Mobil (open til 8pm) and Liberty (supposedly 24.7).
Texas, Qld - Metro (home of the Texas Roadhouse) which is advertised to close at 7pm. There also appears to be 'Fords Family Store' (never visited) which is advertised to be open to 8pm. There is also a hotel (might be good for a DBR if need be).
You do have the option of adding in 'Goondiwindi' which as 24/7 fuel (costing you for an extra 70km).
Narrabri - Looks like there is a Ampol Foodary open til 10pm. Also an Ampol depot with shopfront advertised as 24/7.
Gilgandra - Shell (24/7), Metro (closes 10pm), BP Truckstop (closes 8pm), Inland (Closes 8pm), Ultra (closes 10pm), Ampol Foodary (24/7)
A couple of strategic phone calls prior and you should be good.
You are also currently assuming you can get through around Taree which may not be feasible as there are no bypasses through the town to get north and back onto the highway at the moment with bridges still pending engineering inspection and debris all over the roads (my brother tried getting through Saturday (early) afternoon and ended up getting turned around and having to head back (to Brisbane) via Muswellbrook).
Some nice riding roads up that way (although you appear to be skipping a few) - also some shocking roads too.
Hope the above helps.
Good luck with it.