The so called "Backdoor Roth" does not apply. Backdoor Roth's are done to make Roth *IRA* contributions when ones income prohibits a direct Roth contribution by first contributing a non-deductible contribution to a Traditional *IRA* that has no restrictions and then converting that Traditional IRA to a Roth IRA.
That has nothing to do with 401(k) contributions converted to a Roth 401(k) in plan rollover. What and how much you can convert depends on the 401(k) plan rules - ask the 401(k) trustee.
Once in a Roth 401(k) then that can be rolled into a Roth IRA with no tax. Whether you can roll it to a Roth IRA before retirement age again depends on the 401(k) plan rules for your particular plan.
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.