Two questions:

1. My work week starts on Sunday, so I have:

(setq org-agenda-start-on-weekday 0)

Now the agenda timeline starts on Sunday as desired. However, it says on
top "Week agenda (W34-W35)", i.e. it still thinks that the week starts on
Monday. Can I change that?

2. It would be very useful for me if the weeks were numbered from the week
when my big work project started. Can I have the week numbering customized
to have W01 on a certain date?