UV assessment periods

Please can I ask a question regarding UC assessment periods and payment dates?
The guides states that the ‘assessment period’ runs from month to month, but it also says that payment is always one week after the end of an ‘assessment period’. Sorry I’m just a bit confused - does this mean it is paid every 4 weeks or every 5 weeks? As I understand it, you have to wait 5 weeks initially when applying, before the first payment, but is this then always the case from then on? As I’m just trying to understand how to budget into the future. Thanks