That may be a case for Cypress support.
Thanks for answers,
yes, I saw these documents, but there are no API examples and I'm afraid there are some underwater stones.
In the function comments(Cylib.c) there are mentions that PLL must be stopped before source switching. So, I wonder how to drive uC at this moment.
This ap note shows the chain of actions necessary for controling PLL,
and calls out the registers for manipulation, which would be in register
TRM. Might shed some light on an approach you could try.
And or file a CASE to and post back to forum what you find out.
To file a tech case -
“Create a MyCase”