Does boot image get updated with build updates?

This [article](https://android.gadgethacks.com/how-to/first-10-things-do-after-rooting-your-phone-0384195/) talks about saving a copy of your stock boot image. It was last updated in 2021. > So as you might imagine, if you ever want to **unroot**, you'll need to re-flash the stock version of your boot image. Since you just downloaded a copy of that stock boot image before you patched it and flashed it, now's the time to stash it away for future use. Is this valid? If I ever decide to unroot, can't I download the official build image again from Lineage OS website? It may be a different version by then and work differently, isn't it? Or, **as you update your build version, any changes to the boot image get applied as well**, or is the boot image not affected by OS updates? And on the other end, should I store the patched version of the boot image if I am currently running it for superuser privileges?