What is the subnet that you are using for a gateway? You can choose some other IP address with which you will do the VIP. Can you please share the related configuration for the VIP that you are trying to use? Interface, static route, VIP policy, firewall policy, static route?
Since I am asking you to provide parts of the configuration, some malicious user can read this, so you can mask the real IPs or use trusted host.
Since those are port-mappings, there shouldn't be any conflict for themselves.
Why do you have two static default routes to the same "wan" interface/same circuit? One for dynamic GW and one for static GW? That might be causing problems.
Then run two commands at the top level of CLI tree. to make sure you don't have the same IP in the config statically or in routing-table dynamically. "show | grep -f 27.x.x.116" "get router info routing-t all | grep 27.x.x.116"
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