Yep it’s Oct 1st at 5pm ET for final roster due dates. I do wonder whether in practicality that means the final players cut will physically join the Marlies for practice on Oct 1st or Oct 2nd.
I think the rule is that Leafs have to put players on waivers (if not waiver free) 24 hours before so I expect some movement on Monday 12 pm so that by Tuesday 12 pm these players either clear or get claimed.
The way their contracts are structured (1 way deals) and handsomely paid at that it won't be easy for other teams to claim these and pay the 1 way contracts for these players to play in the minors; leafs on the other hand can afford it
So in terms of reporting for marlies I think that would be on Oct. 1st since these guys have to be put on waivers on Sep 31st (monday).
Not sure if that is also true for the players that do not need to clear waivers ex: Liljegren; that said - since my assumption is that Leafs have to be cap compliant by 5 pm Oct 1st (Tuesday) - most of the players if not on the Leafs roster would be available for the Marlies by oct 1st I think.