Actually I'm not sure that the OP's issue really is the "normal" one that many of us have seen before.
When I've had this in the past, I think it has only been when I've laid in a single jump, and then got heavier (e.g. refuelling at a station or by scooping, or buying cargo).
However, when I've used the galaxy plotter to plot multiple jumps, as far as I've been able to tell it has (most, annoyingly*) always insisted on assuming full fuel tanks for each jump (or maybe each jump
after the very first one, can't quite recall). My experiences don't seem to line up with the OP's though.
[* annoyingly, because there are often better routes available once you allow for the ship getting a few tons lighter with every jump, and I've never found a way to tell the game not to assume a full tank]
Edit: one of the many things that could be done to help debug this,
@Killasandara, is to examine the route before and after the log-out/log-in cycle (I seem to recall that the first few jumps are noted in the journal but you can always just check manually of course) to double check if the route has changed...