Well it certainly is fluid but I’d not like to predict which way.....LH commands used to around the 15 year mark, recently however I’ve flown with several guys who are coming up to 20 years in the RHS and they are not being held back by being particularly selective in what they have bid for.
Logically I suspect you’ll see the time to command slide back down to more normal levels as retirements and a few resignations kick in so those that have already joined might benefit.