On Mar 1 I had to stop the bleeding to keep 2 schedules from running all day so I did a combination of disabling schedules, and adding Var=February conditions to others. But we are talking about maybe ±20 schedules, and since we still can't copy/paste conditions, that's a lot of hacks to add one by one. Especially for something that shouldn't need a hack.
So before I do that, is this a bug that will be fixed, or are you going to keep this date logic?
Being totally honest – it won't be fixed in the near future. Or rather, if we did fix it right now it would just be by disabling the 29th item in the menu when February is selected, which isn't totally correct either. Note you could also change the end date to Feb 28th which would work correctly for as long as it isn't a leap year and even then might work correctly on some leap years depending on how the days of the week fall within the month.
If you are going to keep it, then the user base should be notified of this unexpected result. I doubt many users would assume a Feb schedule could run in Mar.
I agree it is a bug and I've added it to the bug list. That said, this is the first time we have had the issue reported and I think it has been there since version 1 (so 15 years). This, along with the fact that there is a workaround, is why we aren't considering it a high priority bug right now.
Also, are there any other instances in Indigo that we should be aware of that defy logic?
Not that I can think of, but we definitely don't guarantee Indigo to be bug free!