how long to reveg sings?

What happens if you have a bud sickle that was rooted successfully but has been under 24/0 longer than a month and hasn't done anything? I have kept it because it's cool and I don't need the space but just wondering if anyone else had experienced that

Im way new to all this but after reading a few posts I decided to see if I could get something off a harvested plant-chopped it ALL off Nov 1 except for a few bare sticks with baby buds...........NOW 16 days later I have a BUSH after sitting with lights 24 hrs a day...........I did not even RECOGNIZE it when I checked it yesterday