ONe view financial statements

I need rolling month names for Monthly Trial Balance. For example, if the current period is 6, the months should be Jan, Feb, Mar, Apr, May and Jun. If the current period is 9, then the OVFS should show Apr, May, Jun, Jul, Aug and Sep.

If the current period is 3, then the previous 6 months should span to previous year. Example is Oct, Nov, Dec (of previous year) Jan, Feb and Mar of current year.