How to increase the landing accuracy of Q_RTL

ArduPlane VTOL Plane
1

hello. I am a firmware 4.0.9 user.
During the recent flight, the QRTL landing location has been greatly displaced.
Is there any method or parameter to increase the accuracy of auto landing?
If not, is there any way for the pilot to control the plane during vertical descent of the QRTL?

2

With Copter there is a LAND_REPOSITION parameter to control that and allow repositioning is default. I don’t see an equivalent Q parameter. Can you not control it with the Transmitter?

3

The parameter is not visible in plane 4.0.9

4

Transmitter does not work in QRTL