Have you read the instructions? https://www.ftb.ca.gov/forms/2020/2020-100-booklet.html#20_100-4
Is this a first year return?
A corporation that incorporated or qualified through the California SOS to do business in California, is not subject to the minimum franchise tax for its first taxable year and will compute its tax liability by multiplying its state net income by the appropriate tax rate. The corporation will become subject to minimum franchise tax beginning in its second taxable year. This does not apply to corporations that are not qualified by the California SOS, or reorganize solely to avoid payment of their minimum franchise tax.

There is no minimum franchise tax for the following entities:

Corporations that are not incorporated in California, not qualified under the laws of California, and are not doing business in California even though they derive income from California sources. However, if corporations meet the sale, property, or payroll threshold for “doing business” under R&TC Section 23101(b), corporations may be subject to the minimum franchise tax. For more information regarding “doing business,” see General Information A, Franchise or Income Tax; refer to R&TC Section 23101(b); get FTB Pub. 1050, Application and Interpretation of Public Law 86-272; or FTB Pub. 1060, Guide for Corporations Starting Business in California.
Corporations that are not incorporated under the laws of California; whose sole activities in this state are engaging in convention and trade show activities for seven or fewer days during the taxable year; and that do not derive more than $10,000 of gross income reportable to California during the taxable year. These corporations are not “doing business” in California. For more information, get FTB Pub. 1060.
Newly formed or qualified corporations filing an initial return.
Qualified non-profit farm cooperative associations.
Credit unions.
Unincorporated homeowners’ associations.
Exempt homeowners’ associations.
Exempt political organizations.
Exempt organizations.

It is not their 1st year, and yes, I have scoured all sources.  It is a standard S Corp, 3rd year filing.  They have very low income, but was still expecting the 800- minimum fee.  My client said they heard something about the CA government giving a tax break for Covid, but I cannot find ANYTHING that confirms that.  It is calculating a 13- fee, 1.5% of net earnings of 890-.

Any other ideas?