I received this plant on about May 2016; I immediately repotted it (breaking couple of roots in the process) and the plant was like just sitting in the basket like sulking child doing nothing. In later about October, the plant finally began to grow new roots and two new pseudobulbs began to emerge. Then the flower spike appeared in late December and the buds began to open yesterday.
I've read that Coel. assamica is supposed to be summer or autumn blooming species. Perhaps repotting shock has somehow messed up the plant's natural life cycle? Hmm.
Still, quite amazing flower. I like the shape and the brown markings on the lip is great.