N3048P Uboot code on firmware upgrade?

OK, I realise this is knowledge that even a fool should have, however I have yet to level up to idiocy on these switches.....

I have a couple of N3048p switches currently on 6.1.1.7.

I've downloaded and have 6.3.3 and 6.5.4 on a TFTP server ready to upgrade.

Reading the installation notes there are numerous references to the Uboot code requiring upgrade as well, however I don't know if the Uboot code is automatically updated during the firmware upgrade or perhaps part of the CPLD upgrade or is a separate file altogether (which I haven't been able to find on the Dell site)?

If it's part of the CPLD upgrade it would be useful if that was included in the docs.

So, if someone could either tell me, or point me at the specific section I should read Id be greatful.  Please don't just point me at the docs as I already have them and cannot find the answer therein.