This morning I received another one of those emails for my other Biz Plat that I'm planning to close and my spouse received two emails - one for personal plat and for another Biz Plat as well.

So it seems that they're extending it to all plat cards based on aggregate spend. We personally don't use Centurion lounges all that often by ourselves and rarely with guest, but it's good to know that we have this option.