We have to lamb inside here because our fox problem is so severe. Our girls don't actually need to be in, and they dislike it, but we loose some to the foxes otherwise.
Yes- the fox will still be around in June, especially if you have a vixen that's had cubs. Also keep an eye out for crows that want some little lamb eyeballs

Get someone out to shoot them and hope no more move in would be my advice.
People say you can try putting a blob of Stockholm tar on the lambs necks once they're bonded with mum. The stink supposedly puts the fox off, but I'd worry it'd put the ewe off too!
