<span style="color:#323232;">Last-month rule. Under the last-month rule, if you are an eligible individual on the first day of the last month of your tax year (December 1 for most taxpayers), you are considered an eligible individual for the entire year.
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In a 401k one generally does not have a choice in management.
You may have a choice in only a few funds…. So yeah if your holdings were sold then yeah that sucks and hurts. Hence I agree with the top comment IF YOU CAN index funds…