I'm very close to completing the conversion from Bacquacil. How should I determine at what level is best to keep the CYA?

I have a 19200 gal IGV pool.

Fox Wall-Pak filter cartridges.

Most info indicates 30-50 ppm, but I've also seen the posts that say a higher level may not be bad and amount to less FC loss. I was thinking I would start with 30 and see what happens...