RDS CAL User Licensing - 60 days+

Hi

Just quick question regarding licensing and reporting.

if a user that has not logged into to the server for 60 days or more has his RDS CAL sent back into the pool of installed and available licences, when reporting to Microsoft can we ignore this license?

Basically if we have 300 installed but only 230 have been used in the past month, do we raise a PO for 230 CAL licenses used or continue to raise a PO for 300 installed but not used CALS?

Thanks