I am using hnyman's so not sure if it's any different. Netgear R7800 exploration (IPQ8065, QCA9984) - #5 by hnyman
You can use any of those mentioned tools, attendedsysupgrade, owut etc. to sysupgrade to a newer firmware. They would keep the same package selection, but you would lose the minor code-improvents in my build. They are really minor nowadays, as most of my changes have been taken into OpenWrt itself. So, you can use those tools.
Alternatively, download a newer sysupgrade image of my build, and sysupgrade to that.
(The tftp recovery that you for some reason quoted, is just for emergencies, if the R7800 is bricked)