Harvest.
I've seen this before, had one plant keep throwing them out but the trichomes were still changing colour from milky to amber.
Auto is going to keep going till it is mature, if it was a photo you could re veg by throwing back into 18/6. But with auto it will just keep flowering regardless of light schedule, meaning the bud will keep maturing to amber CBN rich from milky THC.
If you got the space and want to see how it progresses...let it roll. Experiments make this half the fun.