update.sh file seems to be out of date

I have been successfully executing the update.sh script, but it will only take me to build 69 on version 1.21.11
From what I have been able to find, papermc changed the way they do auto updates. I tried to use their code to make it work, but I don't really know what I'm doing and I kept getting errors. 

If the update.sh file can be updated, I would be forever grateful!