Dynamics AX 2012 Payroll tax tables

I am looking for information about Dynamics AX 2012 Payroll tax tables.

Can anyone tell me how long it will take for Microsoft to publish the tax update hotfix after the Fed releases the table changes?

Are there any timing issues as to when the hotfix needs to be installed or is it driven by the date?

If the tax table is driven by date, which date?

Are there any other concerns or issues that I should be aware of?

Thanks