Originally Posted by
southlondonphil
As you are travelling from a Non-Schengen Area country to a Schengen Area final destination you will arrive at the 'N' Gates (41-47) in Terminal 1 and pass through Immigration at the upper Red icon where you will be stamped as entering Schengen, then go through a Transfer Security line immediately afterwards which lets into the Schengen area of the terminal and the 'S' Gates from where your flight to FAO will depart (owing to the crippling lack of pier space at LIS this is almost inevitably going to be a 'Bus Gate' departure)

Fast Track = Priority line at the main security checkpoint (lower Red icon) for *G and (some?) other premium ticket holders would have potentially been available to get you from the landside Check-In area to the 'S' zone Departures on your return to the airport if you'd gone downtown but per previous messages it's not really recommended.
Not considering going downtown anymore. Thanks for all the info.