Hello- Is there a way to hide an extension, or a bunch of extensions, from presence? We're using 3CX in conjunction with Algo 8180 speakers for a paging system in our elementary school. Each room's speaker has their own extensions, to allow us to have direct 2 way calls over it, as well as one of them setup as a 'master' for all calls. The issue is we A) don't want all that information cluttering up the softphones and apps, and b) would prefer that someone had to enter a pin code to be able to use the all call. Is the answer to setup page groups? I've read a bit on those, but the documentation was a bit..lacking.