Small update, it dropped a bar since suddenly showing a full tank after previously being 2 bar down on the display.
It dropped a single bar much quicker than it would have if the tank was really full. I would estimate I have done about 20miles since it had the erroneous full reading.
So at this stage I'm hoping it has some kind of temporary error and as the tank goes down it will slowly correct itself. It might take one or two refills perhaps. But I will just monitor for now. No other issues presented.
Looks like it reset itself. Car obviously had a brain fart of some kind.
I noticed that the bars seem to catch-up what i thought the actual level should be. However it did get to a point where I had 1/4 of a tank left and my mileage indicated that it might be close to my normal fill up time, where I may have 1 bar left normally.
So, for a moment, I had the horrible feeling that the gauge had no corrected and the reality was I was nearly empty.
But, it turned out I was just driving efficiently and I did in fact have 1/4 of a tank left.