Ok, I called UBS. For reference, you cannot go to them and pay into a Cardcentre account, that would not have worked.

However, if you pay your credit card bill on the due date (like I am), you will not be charged interest, even if it takes 2-3 working days to arrive. That is how they work, they told me.

Now, it has been a while since I had anything positive to say about UBS, but that is a nice policy I think. Beats the hell out of M-Budget Mastercard who have sent me bills on Friday, expect payment to be in by Monday, which is not possible if you see it Friday evening, and then had the guts to charge me over 20 CHF in interest. Even writing a letter did not help.
So be careful with this card, as they claim payment from Raiffeisen took up to 7 days in some instances! (Which were obviously not due to faults on the bank side of things). Direct debits LSV are also not possible with M-Budget Mastercard, if you want your husband/wife to pay them whilst you are the main card holder and they are partnertcard holders.

Edit: Thanks Rampion, I know that option exists, but I never see it when I am logged in with PF. I only see a priority option, which is different and does not help...