All a bit of a lottery.
Geneva in April absolutely fine, very short queue at immigaration. (Departure from Zurich was fine early morning but horrendous at peak time).
Amsterdam 20 minute wait at immigration. Outbound (off-peak) 1 hour to go through security & immigartion but I heard a passenger complaining about two hour queues. I attived more than four hours before departure. The automated barrier wouldn't let me throuhgh but a kind lady let me through. (Really appreciated! No congestion airside but a bit grim landside.) However the airport seemed quiet on a Tuesday evening.
Heathrow arrivals - T2 20 minutes in April.
T3 a couple of weeks ago at 21:00. Gate available. We had to wait for a marshaller then a 15 minutes delay as the jetty would,t go on. I don't know if this was because we were in a KLM Embraer and the gates weren't designed for such a small aircraft. No queue at immigration at 21:30.
Moral, try and travel at quiet times if possible (which it often isn't).
Last edited by Peter47; 9th Jul 2022 at 18:10.