The Delivery Frequency is 120.35 and if you are delayed just ask us your number in the queue and we`ll give you our best guess. It is usually first come first served although your Company has decided some EK flights are to have priority over others. However there are some other factors that may mean that you get a different start sequence, your SID, your stand, current Flow Control restrictions and recently the weather!
There is no point calling back every 5 mins to check for an update and even less point in trying to jump the queue by changing over to Ground yourself cos you`ll just get put back to Delivery and use up more RT time.