I don't see updates as the problem with openwrt, but its instability.

I have yet to get openwrt to run stable for long, even though I have bought five routers for it by now (WRT1200 was the last). All of them have needed manual reboot at some interval where they suddenly completely died. I gave up and switched to PC Engine's APUs with better luck, but eventually switched to OPNsense on said hardware instead. Much better stability, though not quite as fast with VPN connections.