When do I get a new wife

So Black Jack will need a new wife. But how soon do I do this after his loss? They were so devoted. He is not one for too much stroking he would rather play games, Seams to need more strokes and fuss at the moment. He even gives bunny kisses now. They used to be reserved for his girl.
I am currently giving him a 28 day course of Panacure just incase Thumper's illness was EC related. How do I ensure a new comer is protected against EC?
Any information welcome

You can do it when you feel he is ready, and I would suggest discussing with the person you get that rabbit from (I'm sort of presuming a rescue, but I may be wrong) what happened to the other bunny and see what they say and what they suggest because there is a lot of different advice about EC about, so it will be down to what people in particular feel is appropriate.

Thanks for the reply Sky-o. I will be going on Black Jacks behaviour but it is the EC protection of both buns that concerns me. I guess I may just give a short dose to the new bun of Panacure after she is settled in. Unless the rescue have recently done this. I think I may have to try and find out more about the EC cycle. There does seem to be conflicting information so I will have to read and then just go on gut feeling:?