QB Issue Resolution:

How about creating another new one for Alameda County (CA). This one will be for new 9.5% sales tax rate. You can make the other one inactive when reporting part is done.

Resolution for Issue 'Sales tax in Alameda County went from 9% to 9.5% on April 1,2015 how do I adjust?' available: Yes (Solved).
Source: Intuit Community forum.

Sales tax in Alameda County went from 9% to 9.5% on April 1,2015 how do I adjust?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.

Support for Quickbooks for Mac
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!

Error Recovery for Quickbooks for Mac [Canada]
E-Tech is the #1 Quickbooks data migration and Conversion service provider.

Get 50% off Quickbooks Online

Click Here for 50% off!

Additional Support Options: