I'm very surprised by this as I have booked with a SmartFlyer agent with very good results and extremely fast response time.

Maybe there really has been an emergency or other valid reason for this delayed response.

I would suggest contacting the property GMs as others have also said. Just to confirm that everything is okay, and possibly to make changes to the dates yourself. But, I see no reason to rush to judgement as long as the properties confirm that the bookings are in order.