APM: Static Resource for Variable Assignment?

Has anyone managed to get a variable assignment set as a static resource for APM policy sync? (I"m pretty sure you can't, but someone may have managed it).

 

Failing that, is the view.proxy_addr variable assigment (Required for Horizon View PCoIP proxy in 11.4.1 when using NAT) supported with a FQDN instead of a hard-coded IP?

 

(Because with 3 sites, GTM is used to dispatch between DC's, but moving to 11.4.1 at some stage and would like to implement PCoIP for Horizon View AND policy syncing, but you apparently have to set the view.proxy_addr to the NAT'ed IP address of the VS... And of course there's 3 different IP's... Which are GTM'ed under one FQDN...