Moving back does not mean moving across
Law 8 places the conversion on a line through the place where the try was awarded, parallel to the touchlines. The kicker can choose a position farther back along that line; the award’s sideways position remains relevant.
Imagine two tries at equal distances beyond the try line. One is awarded near the touchline, the other near the posts. Moving both kicks back twenty metres does not erase their different angles. The conversion setup follows where each try was awarded across the field.
Follow the lateral coordinate
A camera tracking the tee backwards may make it look as though the kicker is simply choosing any comfortable point. Look for the imaginary line running lengthwise from the award location. Distance back and angle across are separate features.
This explains the incentive to improve a grounding position when possible, but it is not a prediction of a kicker’s success rate. A close position can still be missed, and a difficult angle can be converted. For interpreting the setup, the useful comparison is geometric: retain the same sideways coordinate while the kicker moves away from the try line.
Questions answered
Can the kicker freely move sideways towards the posts?
The kick must stay on the specified line through the award location.
Does moving back remove the original sideways position?
No.
Sources & further reading
Official references for the subjects discussed. Service terms and device software can change.