Certified GKH Gardening Expert
It could, very well, be that old corms have died. This could leave behind seedlings or plants that have not flowered yet, that can be a different color than the original.
It could, also, be that these are a hybrid, and being an older plant, could mean that genes are breaking down and exposing other traits.
Whichever it is, it will be fun to continue watching to see what happens!
Here is an article for more information on the plant: