Requisition management at end of year

We just upgrade to FIN 9.2, and in our old system we had a small customization in place that would prevent users from being able to run the submit process on a requisition since budget check ran prior to submission into workflow. Now in 9.2 the req appropriately runs through save, submit, approval, and finally can be budget checked. First is there any way you know of to prevent requisitions from budget checking except for by very specific users or roles? And second, how do you handle year end requisition processing? Our biggest issue is where people would put on large requisitions, they would get approved and moved over to the next year, and then they would cancel the req so they could keep the funds they didn't use in the previous year, thereby bypassing our budget limits, so this is why we have this issue in place.