Yes, I've seen this on some of my other slippers and it doesn't usually reoccur. This one has 2 or 3 more buds coming behind this one. I think the flower has developed more blush on either side of the dorsal since this photo was taken too. The flower has a very heavy substance so I'm hoping that means that it's a long lasting bloom.
Finally... a (barbata x cochlo) hybrid... I've been waiting to see one for so long... and I think its really nice... more hybrids like this should be made..!