White-ringed Flycatcher

What about Conopias albovittatus? I think for Boat-billed FC your beak is a little bit too small, as I can see from your long distant shot. But one can see perfectly the white ring around the head, so that's the reason I think this one might be Conopias albovittatus. Usually these birds turn the head always that way that you can't see the ring and separating from Socia Flycatcher is tricky. But I am not 100% sure, you have to verify!