To move data from one time frame to another in the budget, select the Period icon from Tool Bar and choose Move Period to reveal the following screen.
By placing the mouse pointer in the centre of the green bar (a hand will appear) you can move the period of the budget without changing the period length (i.e. Jul to Jun moved forward one month becomes Aug to Sep).
This will move any data from the original time period to the new time period.
See also To Load Actual Transactions