My guardian farm, built back in version 1.8, now has guardians spawning outside the previous temples bounding box to the North and West up to nearest chunk border.

Updated info as requested: Seed= -8159456647961895926   Coords: -880 112

1.17.1 world save: https://drive.google.com/file/d/1js7HGS9LgwT_5K1-cIHLg9V4m0EMQk6d/view?usp=sharing 
The world was originally created in 1.8.1 and has been updated throughout the years.