Destroy all herms, no exceptions. Do not try to save them from themselves. Any plant pollinated will have less potency and yield.
With fem seeds I learned early on to plant an extra seed, so if the time came a herm popped up I would have enough plants going that losing one will not hurt my expected yield, if not I'd just have to fit in another plant. But out of 100+ fem seeds only three herms, so if you keep a good environment the rare genetic induced herm will not show up often. I mostly clone now unless I want to try a strain we don't have active so herms are not a worry but I still do weekly inspections from week 1-4 of flower. But most herms, especially ones that end up having many pollen sacs, should be able to be seen in late veg or very early flower. Herms tend to have weak, softer branches and will often be very stubborn to show sex.