I don't think I wrote that. (edit: okay, so I did, meaning the fuel is unending)
I've considered that the amount of fuel burned could be too little, but semi-dismissed it and decided to post the bug report in Academy just in case.
I've had fuelers following a bigger corvette group on training and refueling took several % per refueling.
Tanker 1,000 kiloLitres, corvettes (10 kL*9) 90 KL : <1% fuel, but repeated about ten times onroute to the precursor infestation. Also the tanker is using fuel as well, so I'd not have expexted all of them to have them arrived at destination at 100% fuel.
edit2:
tested it explicitly with 1 tanker (98%of 1ML) and 14 corvettes (100%of 10kL): I get a orders complete message, the fleet is someplace halfway to its target, orders are cancelled and ALL ships in TG now have 100% fuel.