Club distance is influenced by many things - spin applied, wind strength/direction, the slope you land on, the firmness of the course (St Andrews is very firm and rolls well if you hit the right slope, others not so much), overall elevation change (a drive hit severely uphill will generally have less carry but more roll, while the opposite is true for severe downhill elevation changes), and the ball you use just to name a few factors.
Also some game types do not allow apparel bonuses, so depending on what you were playing maybe your "boost" was active one game and not the next?
I would say 284-300yds for a 280yd driver is right about what I'd expect, sometimes even in the 270s if you were hitting into a strong headwind or more if you were hitting downhill with a good tailwind.