If replace a region with automation off and you had automation written on top of said region, automation will be stripped...

from the User Manual:
"Replacing MT Entries! Placing the MT Cursor on an entry and pressing [Shift-R] will replace the entry with the currently
selected Region Listbox region. If Automation Mode is active when you engage the operation,
automation entries are preserved."

I didn't realize this until today...it's amazing how there is so much to learn...and I can see this as an excellent way to strip automation
altho, there are many, many ways to strip automation in SS

In my work, 95% of my automation in SAW MT is purposefully placed within region boundaries to keep the automation sync'd
to the audio...so, if the region gets moved...automation goes with the audio