I'm booking DFW to DXB for November (of 2021) on EK222. When searching on the Emirates site, some days show this flight operating with the 777-200LR & others show the 777-300ER. How reliable is this info at this point? Or is trying to schedule based on the operating equipment just a crapshoot? I'm booking J, so I'd prefer to be on the 200LR.