As you move teams for regrading, you can choose to include results from their original grade, however, both the former ladder (if the team comes from another grade) and the new ladder can be affected.
This article addresses the impact regrading may have against the ladder of the grade to which the regrade has been applied.
To help with ladder impacts, on the regrading page (see screen image below), the ladder displayed on the right-hand side shows the latest results based on the current round for each grade:
Adjusting Ladder Results
PlayHQ allows you to choose which round you would like to start calculating ladder results from, and whether or not you'd like to include results only from games played in the grade. You can also choose to begin a ladder's calculation from a given round.
To change these settings, select the Competition Management main menu item, and then the appropriate Competition and Season tile, and then view the Grades tab. Select the grade, then the Settings tab, and finally the Ladder sub-tab: