When to take new growth out of bag?

Hello,
I kept rootless dendrobium cane ziplocked in a bag with sphagnum and it produced some new growth which now shows some roots. When should I take it out of the bag and place into pot? I noticed that one leaf on the old cane started to get yellow and there are black spots on the stem.
Thank you very much.

[King_of_orchid_growing:)]

That can be removed from the bag already, but you can't pot it.

You can mount it without using moss though.

Make sure the humidity is at least 50%.

Thanks a lot for the info. I took it out of the bag. Hope it will grow.