How can I extract dates from a string and use it to validate the rest of the string (key date)

Hey, I have an excel sheet with following content in 1 column.

Formate:

Date > Date (period in which the following number is valid)

Number

or

Date > … (open end period, so the following number is always valid)

Number

… (most of the time 1 Date - Number combination, but sometimes more like in the screenshot)

I want to manipulate the excel, so this column is replaced with one, that has only the valid number (on a certain key date) in it, if no number is valid leave the cell blank.

So i thought of splitting the cell (delimiter ), convert the date columns and analize for matching Dates → key date is in the period; but i cant find further steps to implement this idea.

Does anybody know how to implement this or even got a better idea?

• Screenshot with example cells:

Cell above marked one is shown wrong. There is a between … & +1D6

Thanks a lot!