Hiring a total of 400 new pilots in 2018 is very good.
If they maintain 30% of the hires will come from Horizon (120 or so), that will be comperable to the American and Delta Wholely Owned RJs, a flow rate of about 6 years.
With Horizon already short of pilots and cancelling flights this summer and fall due to pilot shortage, this could turn into a bigger crisis for them. They will have to make changes to be competitive!