Inbound IP Passthrough Activity Not Acting as Intended on Device Firmware [RESOLVED]

NOTE: This issue is resolved as of the 18.4.54.41 release.

Problem

Unable to send inbound traffic from an external source to the cellular IP (IE: ping) of an Accelerated cellular device on firmware 18.4.54.22 configured with IP Passthrough

Background

We've been seeing an issue where the latest firmware has unintentionally engaged the firewall for passthrough connections. This results in failed pings from an external source of the cellular IP of an Accelerated cellular device on firmware 18.4.54.22 configured with IP Passthrough.

IP Passthrough Knowledge Article: http://kb.accelerated.com/m/67105/l/745871-lan-port-with-ip-passthrough

Manual Solution

On firmware 18.4.54.22, a change can be made to the Packet Filter's config (Firewall > Packet filtering > Allow all outgoing traffic > Source Zone > Change to "Any" instead of "Internal").  This is the intended passthrough functionality and how it operates on firmware versions 18.1 and prior.

The unintentional engagement of the firewall for passthrough connections will be addressed in a subsequent firmware release.