Yea i checked the servos but didnt see anything that might round robin the items. Could have missed something but yea i dont know. I know i saw a mod not long ago for 1.12 that had round robin pipes but just cant remember the name of the mod. Been going through the mods on curseforge but cant seem to find it.
Buildcraft additional objects has round robin pipes. Pipes that change output with each item going through. Also regular buildcraft as round-robin extraction pipe which let's you extract items from inventory in an order