I found a bug while switching through the different payment gateways.
When I switch from a PayPal Plus Gateway to BACS and then back to PayPal Plus (e.g. Credit Card) the selected is method is correctly checked.
But when I submit the order I get directly redirected to the thank you page, instead of the PayPal Website. On the thank you page (and the wordpress backend) I can see that the order is saved with BACS Gateway.