tailBeaconX Must Not Respond to ATCRBS/Mode S ALL-Calls (Long P4 interrogation)

In July 2014, the International Civil Aviation Organization (ICAO) Released Annex 10 Volume IV, which defines Surveillance and Collision Avoidance Systems. Essentially all countries are signatories to ICAO and must follow their guidance. The updates in Volume IV required countries to stop interrogating Mode A/C/S all-calls and to stop certifying equipment that replied to those interrogations after 1/1/2020:

Test sets that require response to Mode A/C/S all-calls, likely ones manufactured prior to 2015, may indicate failures during automated test passes. Unfortunately, this equipment will require updates to properly test any transponder certified after 1/1/2020.