As per calculation rule every monday requirement will created,
In the case of non working day system will consider the previous working day and create the order.
As you had couple of period set with firmed indicator, so remove all the firmed indicator first then save the planning calendar and again go to change mode and recalculate the factory calendar rules and check the period. Make sure all your blocking date should not populated in planning calendar period
How you block the planning calendar date?
Please check the above step and revert
Planning Calendar Calculation Rule detail information
Please check the planning calendar document in details for your requirement
Regards
Umesh Mali