Puzzled of auto-generated interface routing rules (ip4table)

I want to make one Wi-Fi network to route over WAN connection, and another Wi-Fi network to route over VPN connection.

For this, I've created additional Wi-Fi AP, which is configured for additional interface (in OpenWrt terms). The network has "Override IPv4 routing table" (ip4table) set to 1000.

The auto-generated ip rule's for such configuration is as follows:

# ip rule
0:      from all lookup local 
10000:  from 192.168.12.1 lookup 1000 
20000:  from all to 192.168.12.1/24 lookup 1000 
32766:  from all lookup main 
32767:  from all lookup default 
90007:  from all iif lo lookup 1000 

To make it work properly, I also need to add additional from 192.168.12.0/24 lookup 1000 or iif br-vpn lookup 1000.
I've omitted VPN interface configuration for now, as it doesn't matter for the question.

Question: is is expected that auto-generated ruleset does not cover the whole configured interface IP range (incl. subnet), or is it intended?
The docs/guide-user/network/routing/basics vague mentions that 10000 and 20000 priority covers "each local address" and "each local subnet", which is technically correct, but is this expected/intended behavior?

In other words, do I really need to handle this configuration with additional manually added rules to make it work?

OpenWrt SNAPSHOT r25671-29515862ac / LuCI Master git-24.077.26240~f2a4910

Gentle bump