Carrot fly

Can anyone suggest to me when I can remove my veggiemesh from my carrot crop,without running the risk of fly laying their eggs.I live in mid west wales and am starting to "put stuff away" for winter,and having forecast a dry colder week,wished to take advantage to store my mesh when dry.
The carrots are lovely and clean and a good crop too,alongside our protected parsnips.
Regards  John.