Although I couldn't find an official changelog, here are some potential features and improvements that might be included in the H3Q44 V3.0 firmware:
Flashing the wrong firmware can "brick" your device (make it unbootable). Before you start, open the box and check: Wi-Fi Chip: h3q44 v3.0 firmware
The new firewall in v3.0 sometimes drops ICMPv6. Solution: Add an IPv6 firewall rule allowing ipv6-icmp (types 1,2,3,4,128,129) on the WAN interface. Although I couldn't find an official changelog, here
: Often labeled as Android 9.0 or 10.1 (though frequently "fake" versions masking Android 7.1) Wi-Fi Module : Optimized for the SV6256P chip h3q44 v3.0 firmware