Periodic snapshot fact table with monthly grain - Question on dimensions

I am fairly new to data-warehousing but have read my fair share of books and online tutorials to gain an introductory understanding of the basic components that build up a data warehouse.

My end goal is to be able to do a headcount of employees at the end of the month, therefore I designed my fact table as a monthly snapshot where each end-of-month I will populate my fact table (one row per employee per month).

My dimension table includes a DimEmployee table which is an SCD2 (any change made to an employee's information causes a new row to be introduced in the data source and I am keeping track of the most recent employee information via an is_current flag set to 'Y' or 'N').

My question is: do I need to update the dimensions daily and only insert whatever data I have at end-of-month into the fact table? Or do I update the dimensions end-of-month as well?