What is the range of potential life sentences for the attempted first degree murder conviction?

For the attempted first degree murder conviction (count 1), the probation report recommended a total term of 55 years to life. The exposure calculation chart in the report states the term for count 1 is "replaced by associated enhancement," which enhancement is listed as "PC 186.22(b)(5)." At the sentencing hearing, the prosecutor provided the court with a proposed sentence and defense counsel submitted. Based on the probation report's recommendation and counsel's own research, the prosecutor recommended for "[c]ount 1 for the 664/187 . . . raising [it] to 15 to life because of the 186.22(b)," then doubling the 15-year indeterminate sentence to a 30-year indeterminate sentence based on defendant's prior strike conviction. The prosecutor indicated this calculation was supported by People v. Jefferson (1999) 21 Cal.4th 86. The prosecutor also recommended adding 25 years to life to count 1, for the section 12022.53 firearm enhancement.