Note that EK will need to recalculate fare at origin. So do it at the airport - if seats are still available.
I don't know what fare you paid.. but the cheapest roundtrip from GLA to DXB in Business is around GBP 1222. So you have to take the difference between the two.. but as that fare has advance purchase conditions, that is why EK wants you to do the upgrade before you go to the airport. Cos at the airport, they may just charge you the full oneway Biz fare for around GBP 2080.
If its not too far, try going to the EK ticketing office (in town or at the airport) and explain the situation to them. They might be able to calculate what the fare diff is and upgrade you there.
Last edited by Guy Betsy; Jul 5, 2012 at 4:56 am