Hi folks and thank you so much for sharing your feedback.
I’m excited to announce that the Timeline now respects the “first day of the week” you have selected in your Profile settings 
This new update is already available to all our customers, so if you haven’t yet, open your project timelines to check it out 
This update is currently only available on Timeline (we’re yet to implement it on the calendar view), but I hope you enjoy this first update. I’m keeping this thread open and will post an update here as soon as this option is rolled out on the calendar view!