Commonly beard cycles are shorter than 8 weeks and it’s common that treatments are done 4-6 weeks on face. But if you’re not seeing any growth within 6 weeks then yes I would wait until there is visible hair to treat. You just need to stick to a consistent schedule, spaced out equally.
You need hairs growing in order to remove them. Ideally You wait until the next steady state is reached. For beard hairs that usually takes longer than just 6 weeks.
That’s why i suggest longer intervals of at least 8 weeks, better 12 weeks or even longer between clearances of even electrolysis.
When i did my 12 IPL facial IPL sessions the operator urged me better to do intervals of 8 weeks at least, in later stages 10 weeks. Intervals shorter than those 8-10 weeks in Laser or IPL treatments serve only one purpose: fill the pockets of the owner of the studio.