Hi ,
Welcome to this Microsoft Project newsgroup
In the Resource Sheet view, double-click the resource and in the dialog you
can enter the Max Units and the date of change, but you have to do it
manually, there is no calendar the takes Max Units. I would recommend
splitting the resource into two and setting up a separate calendar for the
resources that work on Saturdays.
FAQs, companion products and other useful Project information can be seen at
this web address:
http://project.mvps.org/faqs.htm
Hope this helps - please let us know how you get on
Mike Glen
MS Project MVP
See
http://tinyurl.com/2xbhc for Project Tutorials