We've replaced all previous scheduling with two shifts - 8am to 2pm, 2pm to 8pm - each with half of our staff and with as little contact as possible between them during shift changes.  This is so if we do have someone on the staff or a patron visitor (eventually) become infected, we can quarantine just the affected team.  This is safer for the staff and for library contingency planning.  We have at least two building leads (those who have been before and are familiar being in charge of the building for opening, closing, or weekend schedules) on each team.  Myself and my department heads are the two designated PIC or Supervisor for the two shifts, but the leads could be designated in our stead.  However, I think they have to be familiar with all the procedures mentioned in the required reopening, cleaning, staff safety, and preparedness plans.  

That's how I understood it, but there are others with more specific knowledge.