Can i set the calendar to 28 day minimum?

THe calendar is not limited to 7.

Simply open the list view ,expand each room type, then each rate plan and promo, 

now edit or bulk edit the minimum stay to 28 for a date range

Simply report to BdC Partner Support , see below 3 methods. They will never see any post on the Partner Hub.

Message or Call BdC PartnerSupport 

1. In the extranet, go to the ‘Inbox’ tab.
2. Select ‘Booking.com messages’.
3. Right Pane - Click on ‘See Contact Options’. 
4. Choose Account
5. Now choose Other
6. Then at bottom , See all contact options, and click Message or Call
7. As there is no one number for all partners, the number for your nearest BdC Partner Support is then revealed.

8.  

   *** public main lines via Where you can reach us

    

    

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