Careful on the wording here so as to not generate a confusing and false mandate. There is zero obligation of any kind to check your schedule on your day off.

Period.

Full stop.

The 3PM thing is really a 9 hours prior thing, which is really a relic of a holdover from the previous contract that's still in there. Basically all that says is that's when THEY have to have anything earlier than noon finalized and on your line. If they do that by 3PM (or whenever 9 hours prior is, if its an irregular partial payback day, etc) then they can take noon down to as early as 10AM. But never earlier.

Therefore its cool on your end to get a 3PM-ish heads up as to what you'll be doing, but you absolutely do NOT have to check it at or prior to that time. If you want, you can be radio silent/blackout til midnight, as long as you can then be in position to do something as early as 10AM.