UTM Dropping HTTPS - Can't Ignore MTU Settings From Internet Provider

Good Evening,

So it seems with the latest firmware update that I cannot change the MTU setting being provided by Charter.  The setting received is 576 and when I change it in GUI to 1500 after the update, it automatically changes it back to 576.  In the past you could edit this file and that is in place, but not being used after the new update.  So now Im seeing the same thing with ALOT of https traffic being intermittently dropped, but no way to manually edit this.  Any ideas on how to fix this?

Here is the post on bad bugfix to ignore MTU setting from provider.  

https://community.sophos.com/products/unified-threat-management/f/hardware-installation-up2date-licensing/79288/disable-bad-bugfix-in-9-405-5-fix-nutm-2840-aws-utm-ignores-mtu-sent-by-dhcp-server

https://community.sophos.com/products/unified-threat-management/f/network-protection-firewall-nat-qos-ips/79344/https-traffic-dropped/303122#303122