There is no limit on how much money a tenant can send into their wallet. So if a tenant wants to pay rent in advance, they can send that money into their wallet using their unique payment details.
When the funds arrive, they won't be used to pay rent automatically as the app only auto-pays when rent or bills are due.
To push that payment through, you can click 'prioritise' next to the rental payments. You may need to refresh the transactions tab each time you prioritise so the app generated the next period for you to prioritise.