We are having the same issues with SAM. The blue band occurs when the times aren't entered, just the date. If you then make any amendments to any absence in SAM, it doesn't transfer to SIMS. Only new absences transfer. We are waiting for a solution from SAM - now been going on for weeks. Wonde have checked at their end and data is being transferred but SAM don't know why it's not writing back.
Let us know how you get on and if you get a response from SAM.