Android OS using excessive mobile data after upgrade to 5.0

[andydba1]

I sideloaded the update yesterday and have noticed today that I was using way more mobile data than I normally do on a workday. I am on Wifi all day at work and rarely use any mobile data. Today I have used almost 200 mb of data it looks like it is coming from Android OS.
Any ideas? I am currently on a limited data plan, so this is obviously not sustainable. Thanks