I don’t know how many sims are being discussed as being necessary, but lets assume 5 training, plus a check, so 6 per pilot. I would be surprised if it’s less, but it wouldn’t expect it to be much more. Assuming 100% utilisation of the sim, then you’d basically be able to produce 1 two man crew per day. Of course the sims are never up 100%, they aren’t themselves manned that way (i.e. sim instructors and senior checks), and I’m not accounting for SOs. I expect the real rate would be more like one crew every two days. With 10 aircraft, you’d have about 70 crews. So, 140 days just to cover the sim work.
But, once you start churning crews out, they’ll need recurrent sims, so, that will start to eat into the available sim time.
Restarting will be difficult, in so many ways.