I emailed Fort about the serial number on my frame and apparently FO means it is a Fort and the first number is the year it was made. So mine was FO5**** (so FO then 5 numbers like yours) and that meant my frame was from 2005.
@irish_mick started
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I emailed Fort about the serial number on my frame and apparently FO means it is a Fort and the first number is the year it was made. So mine was FO5**** (so FO then 5 numbers like yours) and that meant my frame was from 2005.