Assuming that you are reffering to the TLS agents that connect to the JCP and not the CP anymore, the old ping messages are no longer used (Last Checked column not updated), regardless of the srvquery setting. The TLS agents use a Websocket Ping message with the default of 60 seconds and can be changed in UC_SYSTEM_SETTINGS as described in the documentation https://docs.automic.com/documentation/webhelp/english/ALL/components/DOCU/21.0.5/Automic%20Automation%20Guides/Content/AWA/Variables/UC_SYSTEM_SETTINGS/UC_SYSTEM_WEBSOCKET_TIMEOUT.htm.
Hope this helps,
Oana