Excel: Dynamic range within certain rows + data validation update

Question

What I have here is small part of my big data set, with lot of drop downs and functions that are calculating everything around. I am just exceeding this table and trying to make it more automatically than it was before, but I stuck on that part that I put in green.

Which function might be suitable when I wanna add some new cells on the right (right table) named Model Options > instead of Reserviert but some another name (will be populated later), but to automatically recognize it on left drop down reference cell (Model)? I will have some additional workbook which is gonna be updated frequently, and from that workbook I have to lookup everything what is "new" and to populate it here in certain order like in this two small examples..

Up till now I managed to find OFFSET and INDEX functions:

=OFFSET(Sheet1!$B$1;1;0;COUNTA(Sheet1!$B:$B)-1;2) or `=$A$2:INDEX($A:$A,COUNTA($A:$A))`

..but it didnt work. My Data set (Columns T and U) are not starting from the top rows, but somewhere in the middle (other data is before and after it), and that gives me trouble especially when I am including new rows...

Hopefully I was clear with question.

Answer 1

Well, you dont have to use full column ranges.

For the first list you just have to add a COUNTBLANK in the OFFSET, so that list skips the blank cells. This won't work for blank cells in between the data entries.

=OFFSET(T14:T18,COUNTBLANK(T14:T18),,COUNTA(T14:T18)) 

As for the second list you can use

=OFFSET(Tabelle1!T20:T26,,,COUNTA(Tabelle1!U20:U26))

Here I used the code column to count the number of entries. You can shift it over to the endpoint column by modifying the ranges in the COUNTA-function. This is just to show of some further possibilities.

Hopefully i was clear with my answer. :) If i didn't hit the spot, let me know.