Does FUE permanently remove grafts for future procedures?

I have had FUE procedure 2 months ago and was thinking of having another for my beard. Was curious how long I’d have to wait before another one, and whether the back of my hair could be used again for my beard. I came across some articles that really concerned me, mainly about most people have a limited amount of grafts they could use in their lifetimes, usually around ~4-6k Some remarks...

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