Rental income and paye

2018 were paye until aug. Rented house then. Did tax return at end of 2018 and declared rent so all okay. House rented 2019 from Jan to Aug then moved back in. Will be paye worker. Not sure when we need to declare and pay.

Any time between January and October 2020

So do I do it as a paye return at end of year or do I lodge as self assessed.