Image texture sequence not repeating

I have an 18-frame image sequence that I mapped to a plane in Blender 2.79. In the node editor it’s set to “Image Sequence” and the “Cyclic” checkbox is checked, but the sequence only plays through once before erroring out to that ugly purple color. In the side panel it says “Can’t Load Image”.

Am I missing something obvious? My gut tells me this is a bug but I don’t want to open a ticket if it’s not.

EDIT: I’m an idiot. I set the length of the sequence to the length of my timeline, not the length of the image sequence. Boom, problem fixed.