Big Sur Update Media

How to Create a Bootable Installer if done can be reused to upgrade all machines. It would involve a successful attempt on the first attempt - the full installer of Big Sur is 12.18 GB or 50% of month usage form ISP. Should mention, have read many people, have had to try several times to get it downloaded successfully. Does one have a friend, relative or associate who has larger ISP Cap who might assist in creating the USB Installer?

There hasn't been anything like that in about 15 years.

With Big Sur, Apple has apparently stopped providing downloadable update files, also.

In the Sharing System Preferences, you could try turning on Content Caching on one of your Macs, then theoretically, that will host the updates that the other Macs will use. However, I can't tell you how to force your other Macs to use it as opposed to going to Apple's servers.