Recurring Invoices - Difference between Monthly and 4 weeks?

Just wondering if there was any specific difference in logic between the ‘Monthly’ and ‘Four weeks’ options for recurring invoices? Couldn’t find anything here or in the docs.

Thanks in advance for any help in clarifying.

Hi There,

Monthly calculates Date to date by calendar month

1st of July
1st of August
1st of September

Every 4 weeks calculates exactly ever 4x7 days.