Repeat techniques two to 4 for your entire outdated BRK alarms. We suggest changing all alarms inside the system alongside one another to keep up ideal program operation; failing to do so may perhaps compromise interlink performance. 02 will require for being up to date by 30th September 2021 in https://www.firesense.co.uk/type/addressable-fire-system/addressable-fire-alarm-control-panels/