I never said anything about changing the certifiaction of the plane. Thats EXACTLY what i said, an operator.
If the ops specs say the operation needs a SIC....then you get an SIC.
Exactly true! One example: Back in its early days, Comair crashed a Navajo being flown single-pilot and killed 8 folks. After the dust settled Comair's Part 135 autopilot authorization was withdrawn and a qualified SIC was required on every Part 135 flight.