You have two sets of circuits wires in same raceway? I'm going to assume conduit! If it is a conduit did you every try reading something off of the conduit, then try isolating that conduit and reading off the conduit, again.
Did you physically re-pull or just reassigned a wire?
I think you got a open short on one leg on maybe even two of the circuits, if you replaced it once that was the wrong leg, or both got ripped open with a bur at coupling or transition point of some sorts and the orginal pull released or made the wire back off of the conduit. The use of the circuit brought back the fault (or touch) with the heating of the wire. With PVC in ground, time would be required for all of the new wire to be covered with the humidity of water in the PVC pipe. Your one week!
Did U walk the length of the pulled out conductor, checking for errors?
Walk it againest and assume where that bur might be, in relationship to the wire and fix the bur.
I think I'd do that first, if not sure pull out all the wires, find da-bur, fix accordingly...
If its PVC feed the other way. Determine and feed so the bell end will recieve the wire last, IE not start at the regular pipe end...
Hope that help, Good Luck!