Recently bought an A1 mini with AMS, which has been generally great. I have been printing various things, but was thinking if the wasted filament during color changes could be further reduced.

I was wondering, if the color change happens on a high layer, why does the prime tower need to be built as high in order to flush when the color change happens? Is it not a good idea to have the prime tower not generated up until the color change is needed, and then start building it on the plate directly?

This would imply z axis movement whenever the color changes, but is it bad for some reason? It would take slightly more time, but the filament change already takes plenty of time so I assume it is not a factor of the already printed model cooling or so. Could it be something like we want to avoid unnecessary Z axis movements to avoid alignment mistakes maybe with the current layer, if the z movement is not considered precise enough?

Or it is just considered that the aavings of building a shorter tower any not that much comparatively? Anyone more knowledgeable has any thoughts?