I agree with Cooking4to about braising it and then I would leave it in the fridge for a day or two to mellow all the flavors and then freeze it. However, it should confit well but I would remove it from the fat when cooked and set aside for a while until the fat has solidified a bit so that the juice in the bottom can be removed and stored separately for gravy later. This juice could become a bit rancid after a while otherwise I think.( Just my opinion) Warm the now clean fat up enough again for you to return the beef and proceed as usual.
Life is like good wine.......best taken with friends x