If I drive as normal and approach a junction where I could slow to the give way line and then accelerate out if it was clear I get a very snatchy gear change. I assume that the auto box has down selected to say 3rd gear (maybe 4th) if any higher then it's not an issue. The only way I can avoid this is to slightly squeeze the accelerator very quickly (blip) before I carry out the normal acceleration, then it's fine.

Any ideas ?

It's in for a service in 2wks so would like to guide them to what it may be if anyone has any ideas ?