Using Sublime Text's Replace function with regex
changes this:
"1997.01.01.";
to this:
"1997.01.03.";"Január";
Find What:
("([0-9]{4})[^0-9]*([0][1])[^0-9]*([0-9]{2})\.";)
Replace With:
\1"Január";
Looks for the dates where month is 01:
([0][1])
It was written for a CSV file that's the reason why we have quotation marks and semicolons in the string.