look at the definitions, they are basically saying you can't count the cost an item until it's actually used.
"Used Inventories" means Inventories held at the end of the Reporting Period for future use in
respect of the F1 Team’s F1 Cars, that have been used in respect of the F1 Team’s F1 Cars in the
Reporting Period, excluding Transitional Carry Over Inventories.
"Unused Inventories" means Inventories held at the end of the Reporting Period for future use in
respect of the F1 Team’s F1 Cars, excluding Transitional Carry Over Inventories and Used Inventories
I believe this is what Toto and his off the truck comment was about, as well as what was mentioned throughout the year by other members of the paddock.