Tax Holidays help consumers by waiving sales tax on items purchased during the time.
BigBusiness lets you skip sales tax on items, if allowed, by clicking the Tax checkbox. Line items on invoices are taxed when the Tax checkbox is checked and not taxed if not.
Unchecking the Tax checkbox for items exempted during a tax holiday changes Taxable Subtotal which changes built-in Sales Taxes as well as Lookups for TaxJar or AvaTax.