Future Periods

I need to set GL periods to Future in Order to allow Budget Entry (Federal Budget in Federal Administrator). In 11.5 this was relatively easy to do, but in 12i it looks if I need to open a new calendar period in order to change the number of future periods. I need to be able to open the future periods for the budget load and then put the number of future periods back to the original setting. Is there any way to do this without opening new periods in 12i.

Thank You