I've been doing a single malt oat whiskey for a while now and started doing a oat sugar head concurrently but then thought why am I wasting grain. I now reuse the grain from my sacrification mash to do a reiterated grain sugarhead in the same genre as the UJSM. Heres a basic outline of the process I'm using currently
I boil the spent grain from my last sugar head strain and then dissolve my sugar (same ratio as UJSM) and put that in my fermenter with say 50% or so of the stillage (warm) from the last sugarhead wash to this I add the spent grain from my mash (I freeze this stuff until needed) and add some hot water. Then when the temperature is between 32 and 27 I pitch with the last sugarhead lees, it seems to be coming along just great :D