Answer:
Technically, yes. The original application was not for what this request represents. The multiple parties applied for a loan that was to mature before the extension. You have documentation indicated this is what they wanted. Now, there's a change to the original request (triggering the extension). Do all parties agree to this new arrangement?
With that said, most institutions don't get joint intent documentation on short extensions and it doesn't seem to get cited, in my experience. It's your risk decision.