common, nobody has a tradition chasing cows of their goyishe neighbors for milking. for one, you will get arrested for trespassing and assault. At the same time, Pesach is supposed to be a yomtov when you eat yummy food and have seuda with others.
How was it going during BM? Was your Pesach with matza and maror completely dry? Did you ask people on their gebroks minhagim before registering on the same animal? None of that is mentioned in Gemora as far as I recall. So, if yo would need to cut yor neder when Moschiach come, why not prepare a week early!?