Some ion trajectories involve constant low acceleration. It really adds up time. You accelerate halfway there, then decelerate the rest of the way.

The dawn spacecraft mission to ceres has 48,000+ hours of gentle acceleration under ion propulsion. That’s 5.5 years of firing. But it gets over 38,620 km/h of delta-v (acceleration).

https://www.jpl.nasa.gov/news/nasas-dawn-spacecraft-fires-past-record-for-speed-change/

Most businesses nowadays have a bit of a backlog. It’s more efficient that way, because you can keep the workload at 100%. So my interpretation is that a two week backlog would mean there’s a few other simulations ahead of you in line.

My interpretation is that the two weeks is a backlog. The drag coefficient guys probably have a bunch of models coming in, and they have a bit of an inbox and yours gets in the queue.