I now better understand your problem after rereading it.
Overshooting problem might happen when tail center is not optimal.
I recommend to enter Subtrim (tuning) menu and verify that servo arm is in the middle as close as possible.
If not, use Subtrim CH4 to fix it.
Then make sure that at the same time there is slight angle (3-4°) so that tail slider is closer to the "tail boom". This could already fix the issue.
If not, lowering tail end-points (just one that is closer to the boom) little bit can help.
Too high angle is not helpful, but too low could cause that tail will loose heading completely when too high torque is applied.
So decreasing by step of 10 should be fine. Only decrease until it will be good, not more.