Tp-link wr841n v13 (mediatek) dhcp on wan asks for two IPs

Hello, I'm experiencing strange bahviour with this new router, each reboot WAN interface asks via dhcp for IP with some mac addr and later, maybe after full boot, again from the mac address which I have set in /etc/config/network. And this does even when I have not a spoofed mac addr. Is this a bug?

I haven't did in-depth testing, but I've had issues spoofing my WAN MAC address on a device with an ath9k switch. In my case, it ignored my setting and uses the MAC, or it failed (from recollection).