Thanks for the response Vlasis. We run statistical analysis for FAS in
our production routes.

This request would be for a controlled environment where I am using
GrandStreams 488 to convert from Voip to PSTN. I was thinking that
perhaps FS has a way to allow me somehow access to the Signaling
portion of the protocol. If that was the case, I would be able to hack
my way around it and perhaps ignore the first 200 I receive and not
propagate it to the origination gateway. This is the setup I am
looking at:

A => B => GrandStream Device => PSTN

  SIP   SIP

A/B - Both Gateways

This is a test environment I am using, something I am just playing
with. So in every case I will receive a FAS from the GrandStream
device.

Do you know if there is a way to launch an application from the
DialPlan and have access to intercept Signaling; something that would
allow me to see the messages coming in and make decisions based on
them like propagate or do not propagate that message. I know this is a
tough thing since I am literally asking for access to the SIP Stack.