OK - do you actually know how an airline pricing 'model' works? It's all dependant on fare buckets an availability. It could be that EK has no availability in the cheaper buckets because the flight is selling well.

For example, I just took a random date in the future, MAN-BKK return. Out 2/7/12, back 14/7/12. Prices are as follows :

EK £738
EY £890
QR £962

These were lifted from Expedia.

The fares will most probably go up and down between then.

Cheers,
Rick