Exactly. Before Once Upon a Time would be the best Sunday slot. That would put it in the America's Funniest Home Videos position, but that show has slid around before.
Let me see. Looking at this week's ABC lineup...
Monday at 8 they have Dancing with the Stars. They could pop the Muppets in that slot during its off season unless there's something more important that fills that slot.
Tuesday at 8 they have back to back Fresh Off the Boat. The Muppets could take one of those slots.
Wednesday at 8 they have The Middle. One of the cast, the oldest son, is reportedly leaving that show to be in a CBS pilot. It could be canceled. More room for Muppets as a lead in for Goldbergs and Modern Family.
Thursday at 8 is Grey's Anatomy in its final season. That usually leads into the Shonda Rhimes block of shows. Might not be the best fit, but it'll be open next season.
Friday at 8 and 8:30 they play Last Man Standing and Cristela. That's a dreaded spot that shows usually go to die, but ABC has floated stuff there before for years (hence Last Man Standing and Cristela). It's the least attractive option, but it's an option.
Saturday at 8 they play Shark Tank. That's slid around to different slots before. I feel the same about Saturdays as I do Fridays, but who knows. They could make that a comedy night that leads into SNL. Still not desirable.
Sunday at 7 and 8 they play AFV followed by Once Upon a Time. Again, they could bump AFV to a different slot or bump OUaT to 9 in order to squeeze the Muppets in. Right now 9pm belongs to a short-run series followed by Revenge which is hemorrhaging viewers.
So, there you go. Of course there are a lot of new pilots that will take these prime spots, but the new Muppet Show is a pilot too. There's opportunity. ABC is willing to shoot this, they'd be willing to find a place for it.