Thanks Zol. Assuming that there is availablity on the later date for an upgrade reward, do you know if A) EK will transfer my upgrade to the new flight date or B) i'll lose the upgrade, but not the eco fare, and have to use more miles to upgrade again? My point is, if it costs me another 37,000 miles to upgrade the new eco flight then i wont bother but if costs $100 or something, then i will. The cost of the miles far outweighs the cash in my case.

Thanks