Need to select first part of the string and eliminate rest after a character using REGEXP_SUBSTR

Security Compliance - P2 - United States-Region B
Sales Leadership - Sales Strategy - E1 - United States-Region A
Site Reliability Engineering - M6 - United Kingdom

for example my data in a column looks somewhat like above, i want to use regex_substr() to eliminate everything after P2, E1, and M6 etc which are in the format of 1single capital alphabet and 1 number and its only two characters.

final output looks something like this

Security Compliance
Sales Leadership - Sales Strategy 
Site Reliability Engineering 

>Solution :

I would phrase this using a regex replacement:

SELECT col, REGEXP_REPLACE(col, ' - [A-Z][0-9] -.*', '') AS col_out
FROM yourTable;

This approach has an advantage over a substring approach in the event that any column value does not have the matching pattern, in which case the original value would be selected.