If an employee’s hours are cut and they apply for partial unemployment does that effect the SBA grant or loan eligibility?

It does not affect your SBA EIDL grant or SBA EIDL eligibility. It does not even affect your PPP loan eligibility.

It might affect whether your 8 weeks of PPP expenses (assuming you get a PPP loan) are fully forgiven or partially forgiven. It depends on what your total number of FTEs and your total payroll expenses are between Feb 15 and June 30 of this year compared to what they were during the same period last year.