Any suggestions on how to repot this Leptotes?

[camille1585]

After having failed miserably several times with mounted Leptotes bicolor, I purchased a potted plant about 2 ago. It has grown exceptionally well, and needs repotting, but I'm not too sure how to go about it! And suggestions?

As you can see in the photos, it has grown so many new roots underneath the sphagnum plug that it has been pushing the entire plant up and out of the pot. I'm hesitant to mess with it since it's doing so well, but I need to do something soon.

I was thinking of teasing out some of that old sour sphag, and dropping it into a slightly larger pot with a small amount of fresh sphag, but I'm open to other ideas! (other than mounting it)