Hmmm, yeah, something else to think about, i.e. racing conditions.
Recent race experience is pretty important in being able to judge your level of exertion. Got caught out with this last year when doing a stint of 4 races in October after a break from racing for well over a year. Started too far back, went off too easy in one, too fast in another, etc, etc...
Without some hard racing, i.e. PB attempts, then that experience might not be there to draw on.