Actually, it is based on you on an individual level. Though the punishment itself has been cleared, the loot system goes off of our toxicity reading of the account itself. As such, this account will not be eligible to receive loot again until that hidden level finishes resetting through your continued effort at reform.
Aside from that, it takes both a function of time and games played where no toxicity is exhibited to reduce, and effectively reset, the hidden "toxicity level" of an account.
That said, as each account is unique, even with a hypothetical query of perfect behavior I would not be able to calculate how long that reset would take. The point in cases such as these as the destination is not as important as the journey. Stay focused on being positive in your matches and when you start getting loot you will know you have made it.
This what they told me when I pressed them on it.