xkcd #3232: Countdown Standard
Title text:
Anyone who is caught counting 'three ... two ... one ... zero ... GO!' will be punished with a lifetime of eating only ISO standard food samples.
Transcript:
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Source: https://xkcd.com/3232/
I think scale matters. A year is quite a lot longer than a week or two. It's easy to consider both the next Thursday you're going to encounter and the one after that as subjectively "soon". The same can not be said of a month at least nine months away.
I would agree that your ruleset works on a longer timescale, but not on a shorter one. There's too much ambiguity and crossover for it to work properly. Having exclusivity in definition allows for better communication, especially for something much more personal like something sooner rather than later.