Unfortunately no, I cannot change the billing intervals.
After more than 1 hour!!! While on hold I was informed that Swisscom had switched to monthly billing. The reasons for this are not known.
I was neither informed of the change in advance nor was it explained!! Customer service definitely looks different!
It is an administrative idleness and also economic and ecological nonsense. And a cheek at that! You should have at least informed the customers about the change beforehand!