Boeing737-8.......I certainly don't think the new e-gates will save the amount of time you mention! They are generally problematic when I have used them at various UK airports and an officer still has to be allocated to manually process the many passports that get rejected at the e-gates.
Even arriving at LTN when the old e-gates were supposed to be working was a miserable experience at peak times and I recall once queuing almost as long as the flight from Amsterdam took!