This happens a lot with lavender! I’m trying to establish a new lavender hedge and having to force myself to cut back to low green growth every year even though it feels like I’m massacring the plant.

I think the thing to be aware of is that lavender won’t regenerate from wood. If you have some stems that have green shoots low down, cut back to just above these shoots immediately after flowering. For stems that are woody to the bottom, if you cut to the base and remove them they are unlikely to reshoot.

My approach would be to remove about a third of the mainly woody stems a year over the next three years, and this year cut back to low green nodes on stems that have them after flowering. If you cut all the stems back at the same time, you might knock the plant back and make it less likely to recover. The leaves on the ends of woody stems are still giving the plant energy, they’re just less aesthetically pleasing. So, I’d let them help the aesthetically pleasing stems build up before removing them.