While I don’t blame the schools, I would think twice before accepting a position with schools at the moment. It seems likely they are recruiting teachers on either a temporary basis until their existing teachers and new hires can return, or on a contingency basis if their existing teachers or new hires are unable to arrive or decide not to come.
When you recruit/hire two people for one job it is likely some people are going to get thrown under the bus, either existing and already hired teachers or those now being recruited. Before accepting a position like this, it is probably a good idea to be assured the school plans to throw the existing teachers under the bus before doing so to the new recruits. I suspect many of the job ads we are seeing from agencies are following a similar strategy, recruiting applications in case there is a need to replace existing teachers.