ATC advises

“ATC (air traffic control) advises”

The term is used to prefix a message of noncontrol information when it is relayed to an aircraft by other than an air traffic controller.
References in periodicals archive ?
Per Handbook 4-1-5, waypoints filed in random RNAV routes automatically become compulsory reporting points for the flight unless ATC advises you otherwise.
When ATC advises you to expect a hold or clears you to someplace that's not an airport, start thinking about your options.
Once ATC advises "radar contact," you are still responsible for your obstacle separation on the departure procedure.