I don't inject, so no help there. My butts usually 8-9 lbs have been taking 16-17 hrs @ 250. I would say about 20 hrs based on mine. I'd get them on about 5 or 6 thurs night. You could always start later and up the temp to 300. Like gtr said wrap and cooler them when there done. Better to be done early. Checking temps, that depends on how your drum runs normaly, at holding temps. Just keep it above 225* and your good.
[COLOR=black][COLOR=red][B]Red[/B][/COLOR] [/COLOR]Performer 1993
Green Performer 1998
Super Fast [COLOR=red][B]Red[/B][/COLOR] Thermapen :thumb:
[B]Got butt ? Smoke it !![/B]