0x000D Push Interaction
Op3 Bit 3 - As Continuation
Operand 3, bit 3 appears to insert the specified interaction into the Sim's queue as the next interaction to perform (and not to the end of the queue as usual).
If the inserted action's priority is "max", only the current action is cancelled, any other actions in the queue are not removed.
See the BHAVs "Social - Push Social - As Continuation", "Interaction - Do Homework - From Seated", and many others.
Thanks to Nopke for finding/researching a lot of this.
Hope these notes are of use to someone. Enjoy!