Hi Tami,
Under taxing seems to be a common theme this year. But in all my cases, it has turned out to be related to bonus'. In particular more than one bonus in the year.
I assume you have checked the employee's Tax Credit window? To ensure the amounts were updated correctly? If they weren't check your setup window to ensure those amounts were also updated correctly.
Regarding service packs, yes it sounds like your schedule is one of those really tight ones. It also sounds like you might benefit from a terminal server environment? Or maybe it is time to move to the cloud? It would mean only two installations - server and terminal server. You would not have to come into work as you could likely do this from home!
Debra
PS. I will have to let someone else speak to Manufacturing.