Ignoring whether or not such a recharacterization is permissible, you would report the amount originally contributed to the Roth IRA as a SEP IRA contribution instead, and not report any Roth IRA contribution. Under the circumstances, TurboTax will not prompt you for an explanation statement regarding this, so you will need to prepare an explanation separately and mail it with your tax return since the Form 5498 from the SEP IRA custodian will not show any SEP IRA contribution to corroborate your self-employment contribution deduction. The Form 5498 will only show an recharacterization contribution.
