First time investor, tenant paying early

[Vysakh Sivarajan]

Hello BiggerPockets members,

I got my first unit recently rented out in Nashua New Hampshire and I am dipping my toes into real estate investing. I got a tenant who is now paying his next month's rent too early. He is paying almost half of the rent 20 days early and the rest by the due date. Even though I don't mind getting paid early, the lease agreement says full payment by the due date. Should I just enforce that or just allow to continue ? 

Btw, this website and the forum is just awesome. Everyone seems to encourage others to get better in REI.

- Vysakh