Check to see if there is another junction box as part of the original can fixture, perhaps a foot inside the hole where the can reflector was mounted. If so, the hole may not be plastered over or have light fixture components mounted permanently where you could not reach inside and access what inside that second junction box.
(One morning on WRKO Radio) The tub's not clean! Let's remodel the bathroom.
(One afternoon on WRKO Radio) It's time for an oil change. I'm going to trade in the car for next year's model.