curled oncidium leaves

[Marlena]

I have an apparently healthy, blooming - 2 spikes - oncidium, divided last year. No critters on it, was out all summer on north porch where it had bright light all day and about 3 hours of late afternoon sun. Brought it in to appreciate the flowers. In an east window, misted in the am, watered appropriately. Temp in house is about 77 on a hot day, down to whatever at night, depending on outside temp.

Only on the sections that are blooming the leaves are curled the long way, so they almost form a long tube. None of the other divides have this, but they aren't blooming. Does anyone know what this is? Thanks.