Dubai airspace closed
I heard the same confused message out of Changi last week.
An Emirates aircraft was told by delivery that they should not depart due to Dubai airspace being closed due bad weather!
After a very frustrated conversation the aircraft eventually pushed back. Not common to hear that related to weather prior to a 7 hour flight.
The above threads give me some idea as to how this came about. I will note this for the future. I believe a similar "closure" occurs when there is fog in Dubai also.