I have been playing this game since open-beta and I have never ask this question. Currently you can only have 1 Active Fabrication Engineer DOff sloted. It doesn't matter if its ground or space. I can understand why you don't allow 2 in space and ground. I don't understand why you cannot have 1 Active Fabrication Engineer DOff for space and one for ground at the same time. Space=RSP and ground=Support Drone, comnpletely unrelated.
I know these are not the only DOff with this restriction.
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