Clearwater is the training facility, you start in rookie ball out of HS, then Clearwater in the FSL, then graduate to Lakewood.
If you're in Lakewood at 20-21, you're right on schedule to be in Lehigh at 23.
I think they've become more welcoming to kids the last few years, common sense says 18-22 is the age where you can make the most progress with a prospect, helping them train and mature physically, and fixing any bad habits. It's where I'd focus the majority of my development resources.
COVID created an unusual situation where there were numerous 24-25 year olds with less experience than 22-23 year old prospects normally have, one injury or a late starting college career then a missed season and you're suddenly two years behind in development. I think going forward we'll see fewer late bloomers.