The advance only has to be paid back if the subsequent loan is taken, in which case the grant is considered part of the loan I believe. But if the business ONLY gets the grant up to 10k or 1k per employee that does not in fact need to be paid back. The 150k EIDL that the OP stated was over 30 years @3.75% with the first 12 monthly payments deferred while interest accrues.