I explained my position on auto-updating quite a few times already. Let me repeat it here, in full, one last time.
I won't be implementing any automated update, for multiple different reasons.
1) It puts a responsibility and a liability on my shoulders. If such a system were to be compromised, allowing the push of malicious firmware, it puts me in a difficult position, with potential legal repercussions. Such a system requires the expertise of engineers to completely secure the whole system (which provides a very tempting targets to potential hackers). That means it requires resources, time, and money. I don't have enough of these to put behind what is still just a hobby, done on my spare time.
2) The router is a critical piece of your network. A failed firmware upgrade made automatically means your WHOLE network goes down. If you are currently away from home, you're SOL until you get back home. If you're not an expert, it means you get up one morning, router seems to be dead, and you have no way of properly troubleshooting it (unless you're an expert), leading you to throwing away a 200-300$ router and buying a new one (when it's just a software issue).
3) A firmware update requires a reboot. I've complained enough already against Microsoft for doing so in a very arbitrary manner with Winodws 10. I've personally lost hours of work to one of their automated update-and-reboots because it rebooted my desktop hosting my development VM without any warning (I was working remotely in that VM at that instant). It caused a corruption of my Git filesystem, forcing me to restore from a backup made earlier today, and losing all the work I had been doing between the backup and that instant. Now, imagine a router deciding to reboot itself while in the middle of a very large file transfer. Or while you are watching a streamed movie. It sucks.
4) Occasionally, a firmware upgrade will require a manual power cycle. If you aren't home, it means you are SOL until you get back home to reboot the router.
5) An interrupted firmware upgrade means a router that will no longer work. Do you have a copy of a working firmware on your computer to recover it? If you always let the device automatically upgrade itself, probably not. Means you might be stuck without Internet until you manage to get a working firmware to flash it back. A device so critical that automatically updates itself needs to have a second copy of the firmware, from which to boot in case of failure. Asuswrt does not have such a backup partition.
6) Some firmware upgrades require changing settings, or potentially a factory default reset. Wishing it wasn't the case doesn't make it any less possible.
So no: I will NOT implement an auto-update, for multiple reasons. And while I know that Asus started working on adding it, I still think it's a bad idea with the current architecture. To be done properly, it would require:
1) A second firmware partition, from which to boot in case of a failed update
2) A very secure infrastructure, including a signed firmware image that would only be flashed if the signature is validated
3) Analysis of the current network activity, rebooting only within a specific time period and IF there is next to zero network activity (and that still wouldn't be fool-proof, as you might be doing LAN-side transfer, which would STILL be interrupted if you use the router's four ports as your LAN switch)
4) A more robust update process that would never lead to requiring a manual reboot (the second firmware partition could solve that issue)
5) A more robust configuration system, with developers keeping in mind that you have to ensure that if you change an existing value (for instance radio-related variables), the firmware has to take care of automatically updating these values on the first boot of the new firmware