I got lounge access in Amsterdam.

Basel lounge is a contract one used by specific airlines it seems. KLM Flying Blue gets access if it’s high enough. But not any other SkyTeam member.

Edit. Decided to add more into.

i status matched from OneWorld Silver. In comparison SkyTeam Elite Plus is nowhere near as good. As mentioned below, not paying for all alliance members to get lounge access is poor. Seat selection is also poor. On board, KLM care nothing about non Flying Blue members.

On the plus side, I got a case on KLMs HBO/light fare. And if I want to be optimistic, as it’s extremely unlikely I’ll get the flights needed on SAS to extend this status (living in Switzerland), I can look at it as OneWorld Silver giving me a few months of perks on SkyTeam airlines 😁

And LHR T4 is much faster to exit, picking up a case the way out, than T5.