Hi,
Check the property bag for unitstatus and set the dates accordingly. What date and time you should set, now that's another story, but if you just use new DateTime() you should get the current date.
**Edit** you should be able to do this with a synchronous workflow too, which is easier if you haven't coded plugins Before.
Regards
Rickard Norström Developer CRM-Konsulterna
http://www.crmkonsulterna.se
Swedish Dynamics CRM Forum: http://www.crmforum.se
My Blog: http://rickardnorstrom.blogspot.se