Is this Oncidium ready for S/H?

[Olivia]

I bought this Onc. Heaven Scent "Sweet Baby" a couple months ago and planned to put it in S/H as soon as it had enough new growth. I heard that you should wait until the new pbulbs are half the size of the old one (for new root growth).

It now has four new growths, but I think only one is even close to being at "half" size. But this is my first onc so I'm not really sure. Does the new growth look like it will be able to support the plant if the old roots die off?

To compound things this is my first experiment with S/H... if/when the older roots die off do they need to be removed? I don't want to disturb the plant all the time but what do you typically do with this?

Thanks!

PS - any other S/H advice is greatly appreciated, and yes, I have been studying Ray's website