Set Days Availability in Calendar tab

After I click on calendar grid date the “set days availability” form appears below calendar. It has two fields that are grey – Start Date and End Date. Is there any way to open those greyed-out fields so that one can choose the dates by these two fields and not by using the calendar? It is very cumbersome to use the arrow icon to move month by month. I know there is an arrow by the name of the Month, but the down arrow next to it does not take you to the new chosen month so that is not a working shortcut.

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