I had a similar experience, demand on NBO-DOH was 600 plus, so I setup a 764, after a day or so of game time, I wondered why the route was not picking up as quickly as normal running a circa 300 pax a/c on a route with 600+ demand exclusively. On review, the demand had all but halved.
Similarly NBO-ADD was set to 300 or so, enough to allow me to run to A320s routes a day, it now peaks out at 170.
I was forced to bin the airline and restart, shelving plans for 767s for 321s and 319s for ERJs.
Something definitely seems to have occurred.