I really dont know, I'll let @theatrus or someone else who is more knowledgable on these things speak. All I can say is that now pca9685 will respond to frequency changes correctly (you have to reload reef-pi everytime you change it ).Question regarding the 2.3 pwm fix, my dosing pumps don't move fluid below 50% via the PCA 9685 at the default 1500 Hz, so if I run the update and drop the frequency to say 100 or 200 Hz if my theory is correct, I can expect the pump to work at lower speeds?
Generally it depends upon what type of circuit you are using to feed this pwm and then drive the dosing pumps. Its like a constrain of the intermediate ic /mosfet etc. So depending upon your exact circuit this will vary..
I just prefer to try stuff and fail spectacularly till i succeed.