If I had to file form 8862 will that delay my refund or will it still take the 21 day process?

Filing form 8862, Information To Claim Earned Income Credit After Disallowance, should not delay your refund processing. Once you are accepted, you are on the IRS payment timetable. The IRS issued more than 9 out of 10 refunds to taxpayers in less than 21 days last year.