Ah, apologies, I assumed that was being pressed. Yes that would do it.
If you are ever stuck you can find the step by step instructions on the firmware update thread. That step is in there:
Update Instructions:
Compatibility Note: Your IQ Panel must be on software version 4.2.0 or 4.2.1 or higher and connected to Wi-Fi to install this update wirelessly. Panels running 4.0.0, 4.0.1 or 4.1.0 must be updated to 4.1.1 first, which then can be updated directly to 4.2.0 or 4.2.1. Once updated to 4.2.0 or 4.2.1 they can be updated directly to 4.3.0.
1- Swipe down from the top of the screen and touch “Settings"
2- Touch “Advanced Settings”
3- Enter a valid installer code (default is 1111)
4- Touch “Upgrade Software”
5 -Touch “Patch Tag” and enter the patch iqpanel4.3.0 then touch OK
6- Touch “Upgrade Using Network” (panel must be connected to Wi-Fi). Update will download and install
7- Once complete touch “OK” to reboot the panel. DO NOT TOUCH THE SCREEN. The update process will take
approximately 5 minutes. After the panel reboots the home screen will appear and the LED will turn green.