cycnode
 

So I've got an old bulb that's mostly withered away, the bulb that flowered last year but has no leaves left and a new one growing that's thin but getting taller than the other 2. At which point do I separate any of them from the cluster?

A photo would help a lot. First hand I would not separate them at all. In captivity here Cycnoches and their hybrids have seldom more than 2-3 bulbs.

when i bought it the one was already brown about half way up. i read online that these should be separated into singles during the resting period. will the old bulbs flower again?

Splitting them into singles is not a good idea, so I'd leave that plant whole. Its actively growing so you can water it and fertilize it a lot now.

Oh yeahn fertilizer now too?

Thanks for your post. I saw the title and went to check on mine. It was starting the new growth and needed potted. Mine had two new bulbs growing off two older bulbs so I divided it. Thanks again for the reminder. I kept forgetting it after it went dormant.

Yes, its big enough for water and fertilizer. Just make sure it stays warm.