Whoa I see ok so this OP is about UI side you are on BPM side. If that’s the case I use DB connection string not session. Reason being if you call something from REST you have no session and that Session.AppServerURL is no longer going to work for what you want.
Something like:
bool isProd = Db.ConnectionString.Contains("E10Live");
I’m not sure when they introduced it (at least at 500) but there is also a way to flag in Admin console which system is Production and access that in BPM land (see this post I just made and my prior one Ice.SysCompany.IsLive - #5 by jgiese.wci)