loS latlh je ben
four and additional years ago
(i.e. more than four years ago)
I would accept and understand {loS latlh je ben}, but I imagine not everyone would.
You could consider using {rav} ‘minimum’, as in {rav loS ben} ‘minimum four years ago’, although it might be interpreted as ‘from four years onwards’, i.e. ‘for the last four years’.
qaSpa' loS ben before four years ago occurs
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