Your edits won’t work, and the reasoning goes deep into the workings of Asterisk and how included contexts work. What you want to do is overwrite the exiting context, you need to add it to /etc/asterisk/extensions_override_freepbx.conf and name it identically to the context you are replacing.
Alternatively, you can do what you’ve done in extensions_custom.conf, rename the context to something like [app-chanspy-bhfisher] then create a Custom Destination in FreePBX that goes to:
app-chanspy-bhfisher,555,1
You can then create a new feature code with a Misc Application that points to the custom destination.
OK, miss read that. So my understanding whatever you add to extensions_custom.conf should be included in the dial plan. Apparently it’s not (or not working as expected) Logic tell me Line 31 above should before line 30 to be seen first - but I assume you guys know more than I do
@lgaetz already answered your question in full. I think you are just skimming. You need to stop using the _custom.conf file and use the override.conf file instead. I suggest you fully re-read what he wrote. Take the time to take it all in.
Explanation: Your include happens at line 0. All of your lines are then overridden by the rest of regular app-chanspy. This is why you need to use the override file.