How Much Time I Need To Wait?
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You will need to wait for your oldest ghost(s) to roll off.
The Training and Expert Server requirements were updated within the last few months.
And Aprox. How Much Time I Need To Wait?
You would need to go into your logbook and see what the oldest ghosts “reports” were, it goes back 12 months. As the message states you have too many in the last 12 months.