There's so much heat in Texas that even if ripening is slightly delayed it won't be by much. Last summer I had a net on my Col de Dame Blanc ( late variety in ground) all summer long.
Instead of ripening in October it ripened in November which I thought was later than the previous year, but the birds got none.
Since your trees are in pot, doing this might help prevent root overheating if in full sun. If they are in partial shade then I would put a net close to the ripening season in order to maximize light.