How to upgrade software?

Ok, I have one of the first versions I’ve had for almost two years and am just getting around to taking it out of the box and setting it up. I know there’s been several firmware upgrades since mine was built. For those that have been using yours for a while, Please let me know what I should be looking for (if anything) and let me know how I get thew firmware up to date. I can’t seem to find info on how to do this. Thanks

Here is some info for you

First thing
Check your serial number
You may have a pre-release version
Contact Andrew to verify