Yup. Jefferson would be readmitted and the US would be 50 again. And the Americans in SoCal will want to join Jefferson as it goes.
Finally, some clear and logical thinking from those
outside of the current California. In fact, I would
like to keep the name California and compel the new
nation to change their name. I might suggest North Mexico.
In truth, the secession idea is just a response to Trump
and will be gone when Trump is.