i have 3 plants , the tops are about done. I think I'm gonna harvest them first and then move the light down until the rest of the buds are done is this a common thing. this strain obviously does not finish all at once.
I have removed the faster finishing top colas before harvesting the rest of the plant. It allows the bottom buds to get the light exposure they need to crystal up and have their pistils change color. I would recommend you do it, but like others said, don't bother if you have another group of vegged plants ready to flower, some seedlings ready to go, etc.