[codingdave]

Having full knowledge of the work is not the same thing as full knowledge of the system. Being able to step in to do the work of one of your people is one possible way to provide a safety net for the bus factor, yes. But not the only way, and I'd argue it is not the best way.

This is your team - you are managing them, not the other way around, so if they have expectations of you that are incorrect, then fix those expectations. If you are not technical, tell them so. Communicate your needs and expectations, and then let them do the work. If there is a bus factor that is too high of a risk for a sustainable team, cross-train the team to remove the bus factor. Have a sense of the priority of all the work so that if someone quits, you can re-arrange the schedule, not be forced to jump in and put out a fire.

At the same time, be building up your people so that they can jump in and replace you. After all, if you cannot be replaced, you cannot be promoted either. Don't pigeon-hole yourself into a front-line manager role unless you truly love it. Grow your team, but grow yourself at the same time.