Chaining ifup hooks/hotplug events?

Installing and Using OpenWrt
1

I can not really pin point the issue but just observed that my ifup hook for a Wireguard interface which sets an NPT ip6tables rule on pppoe-wan is not done on every reboot properly.
So right now I just have an cronjob every minute to check for that rule and if it is not present the WG interface is restarted so the interface and corresponding ip6tables rule should be there.

My question is, can I somehow influence the ordering how interfaces are brought up or how to sanly delay an ifup hook? The cronjob works but somehow feels hacky...

2

There's no need for iptables since IPv6 NPT is supported by nftables:
https://openwrt.org/docs/guide-user/firewall/fw3_configurations/fw3_nat#ipv6_npt
If necessary, declare the WAN interface statically, replacing network_find_wan6.

Note that you should not use hotplug to customize firewall rules, otherwise it may lead to a race condition with the built-in hotplug script reloading the firewall configuration:
https://github.com/openwrt/firewall4/blob/master/root/etc/hotplug.d/iface/20-firewall