It would be nice to have the label selected region associated with audio track region move over the audio track in real time so that you know where exactly to extend your left or right selection end. Currently, when moving label slected region anchor points, the region does not extend in real time and you have to terminate extending the anchor point to finally see the exact limit of the audio region selected.
I’m not following your description.
Could you give a step by step account of what currently happens, and a step by step of what you would like to happen.
Let’s say you have an audio track you want to edit a region of. You first select the region, then you hit Ctrl-B for associating a label to it in a label track under the audio track. Now if you want to move the selection slightly further on the right or else, by moving the label (of selected region) to the right (with mouse left button pressed down), you can see your selected region moving to right while moving the label to the right but the same selected associated region on the audio track does not move until you release the mouse left button. When you realease it, the audio selected region suddenly jump to the right to align with the label selected region instead of moving with the label in real time. So you will only know you moved to the correct point once the audio selection will have moved. I suggect both (associated) selected regions ont the two tracks (label and audio) move together in the same real time while moving you left button down mouse. Is it clearer ?
Just cklick in the label first - that will select in the label track and the associated audio
then try moving your labels … 
WC
Sorry, I didn’t see you reply soon enough to thank you. Yes, it’s OK now in Audacity release 2.3.2, I see this label+audiotrack moving together in real-time. Perfect! Thanks to the Audacity team for that. 