To initiate a takeover, you start by using a takeover terminal which can be purchased from the rebel outpost for $10,000 .To place the terminal there must be three rebels with 5.56mm weapons standing inside of the APD HQ. Before you attempt to place it make sure that there is not an active federal event.
Once the takeover terminal is placed in the HQ, a notification will be sent to everyone in the area. This will also give the APD a one minute timer warning that the HQ will be taken over. Once the timer is up the takeover will be started and the area around the HQ will be KOS for the APD to rebel and vice-versa. During this time there will also be a red icon when the HQ that is taken over, The red icon can be viewed on your map, The takeover will last for fourteen minutes if the APD does not stop it. Make sure to be careful where you position yourself as the APD has multiple spawn points. Each officer that dies at the takeover has a thirty second timer added to their respawn timer and this adds up all the way to three minutes per officer that dies.