Update Dates or Transfer Table

[giosos]

Hello everyone,
I have some problems to update date or import table with specific dates (sorted)

A point is:
We have meetings every Thursday and Saturday
In Sheet1 I have dates (sorted red November 2014 - December 2015 every Thursday and Saturday) and columns (Rees, Kleve, Wesel) users put in how many person was in meeting each day.
Other user looking in Sheet2 how many person was in meeting each month separately

Problem is:
If I update dates from Sheet2 D1 drop down list (Data validation from Sheet3) and A3=D1 and A4=A3+1 then dates updating but I cant sorting like a Sheet1 dates,
But if A3=D1 and from A3 And don make autofill like a date then when I make update D1, updating only A3, and other dates its still old dates.

Any idea if possible without change Sheet2 table

Thanx A lot