I have recently upgraded our environment to SQL 2012 SP1 with SharePoint 2010 integrated mode. The problem I have is that when we use date parameters in reports once clicking apply or any post back happens the date format in the parameters changes from the correct UK DD/MM/YYYY format to the US MM/DD/YYYY. The report runs correctly however this is confusing users.
Addiitonally default dates added to the parameters always display in the US format when we first open the report.
After browsing the MS social site is has been suggested that this issue was fixed in CU5 but then removed for SP1.