With PenduLib out, I recoded InDemand to make use of the library. (This should actually make it more efficient, as my implementation for timers in PenduLib is cleaner than in InDemand 1.0.) I'll upload the updated InDemand as soon as I can confirm that PenduLib is bug-free.
Also, I got around to checking, and I can confirm that neither Rock nor Ace3 implement the "/in" command. I'm glad to know too; I never thought that belonged in Ace2, a mere addon framework. And as people move away from Ace2 for Rock- and Ace3-updated addons in the next several months, InDemand may see a little more public use.