Q.How Do I Get The Most Butternut Squash From Each Vine
I have a Butternut Squash plant with at least 5 squash on it, 3 rather large and two getting large enough to eat. QUESTION: Would the two smaller ones and perhaps a couple of baby-sized ones get larger faster if I cut off the 3 largest ones? Also, you should add a caveat to this sentence: “Properly stored, your butternut squash harvest should last for three to six months.” I have eaten Butternut AND Spaghetti Squash well over a year old. Yes, they were not as tasty, but I would suggest, “When undamaged and properly stored, your Butternut Squash can be eaten with little loss of quality for 3 to six months and, with some deterioration, as long as a year or more.”

Certified GKH Gardening Expert
Frequent harvesting will produce more fruit as well as regular fertilizing. But I wouldn't cut off the larger ones till they were ripe. These articles have good information:
https://www.gardeningknowhow.com/edible/vegetables/squash/growing-butternut-squash.htm
Congrats on your longtime storage of squash! Regarding our articles, we base our information on university cooperative extension research, which is readily available to the public through their websites and factsheets.