It has been well documented on the Forum, that flights leave from different gates on a daily basis - even the A380s park at different gates.

In terms of walking through the Terminal, it is all mentioned within the thread that remdk helpfully posted.

As such, I will Close this thread and it will eventually merge into the other.

To the OP, I would encourage you to look at the QR Forum Dashboard. Within, you will find answers to the various queries you have posted.

M