This is a simple script that will delete any entries in a sub you have appropriate mod access older than the date you provide.
All you need is python 3 and the praw and psaw modules
You also need to put your (bot) reddit credentials in botData.py.
This script can take a long time to run, depending on the number of content your sub had. It took /r/piracy about 2 weeks to scrub anything older than 6 months in 2019