Up to now, it was up to 2 years or so , but things are changing.
Taking into account the number of DEC on all fleet, and the seniority now, I would say between 4 to 5 years to command on A320.
A few aircrafts are supposed to be delivered but nothing that can influence significantly the upgrade number.
EK should be the same but at least you get a command on a widebody, and you get proper accomodation and you get a pension plan.
Don't know about QR.
Air Arabia or Wanatiya in Kuwait could be an option for quicker command.