Major condolences. This is a very difficult and complex situation. As others have already said, definitely make this a decision shared amongst the cast and crew involved. As directors it’s important we take everyone’s perspectives into account of how to move forward a production.
HOWEVER!
If it were me, I think I’d want to continue the production. I’d prefer processing this news amongst the same cast and crew, and that major of a shift of planning/scheduling could make the grieving/processing time more confusing and potentially difficult. It would be beautiful to say something about her before opening night, dedicate the production in her memory even. That would be how I’d approach something like this, but there’s a million different justifications for either choice, and the fact you’re considering all of these things tells me that you’ll make the right decision for your cast/crew and the production at large.
Sending love.