Of course better primary trainer is going to accelerate the entire process, and let the student pilots to have a smoother transition period
but this is not all plaaf thinks, one thing you may not realize is how cheap training on CJ-6 can be, i remember I read somewhere when CJ-6 production restarted several years ago, it said the flight hour cost for CJ-6 is less than 1000 cny, which is ridiculously as most the cost are fuels. And the build cost for CJ-6 is even more ridiculous, the new CJ-6 for civilian market has all the fancy features like glass cockpit, gps and etc, but plaaf said we don’t want any of these, just the authentic CJ-6 in bare minimum, so the price dropped to just over 100k cny… which is less than 1/10 of a da-20, and given there are so many places plaaf can spend their money, I don’t think they mind to save some cents on primer trainers
this was exactly what happened to Cj-7 back then, so I think in plaaf’s mindset, CJ-6 of course is not ideal, but reach the very minimum, and it’s franking cheap, that means until they got enough JL-10 and J-10s/j-11BS, they probably won’t take primary trainer renovations/upgrades as priority something
Training on CJ-6 is cheap, but you might not end up saving much money if it means having to spend more time on JL-10 because of a difficult transition. Training on JL-10 is likely an order of magnitude more expensive than on CJ-6.
Two recent (2021) articles on the new two trainers system written by engineers from Hongdu and PLAN Equipment Department:
Both articles state that the performance gap between CJ-6 and JL-10 has resulted in prolonged training on JL-10. The first article points out additional flight hours on JL-10 needed for the transition come at the expense of flight hours on weaponry training.
Interestingly the first article claims that the plan for developing a new primary trainer has been postponed. Assuming Hudong wasn't lying to investors in its newest annual report (published well after the first article) when they claimed they're developing a new primary trainer, either the development started after the article was written, or that Hudong's new primary trainer is a self-funded project.