I'm noticing the maint timer doesn't seem to load much anymore after i had to change the siderail to a compliant one at the behest of a vanguard (Fandom Volunteer staff member). I was wondering if you may want to put a delay into it popping up or put it on a loop to search for your timers every second or so and then start your main function like that? this way it would never miss the window to load if the DOM hasn't finished.
By the way, me and lumi did tweak the start time variable to make it in-line with the later maint start date. I didn't think you'd mind since you basically just set it up like a config anyway.