Possible Bug Resulting in invalid UID requests?

Hello,

I am trying to diagnose the origin of some unusual behavior when using
getmail to grab messages from an exchange server via davmail. In short, it
appears that under certain conditions getmail will issue a request to
download a message with a UID given as "*" (asterisk). This appears to
happen when davmail encounters a timeout downloading a message from the
exchange server, but it is difficult to find a simple reproducer. I was
wondering if anyone else had seen similar behavior, with getmail specifying
"*" (asterisk) as a UID.

The corresponding discussion at davmail is here:

https://sourceforge.net/p/davmail/bugs/709/

The detailed logs are available upon request (too big to attach here).
System is getmail 5.13 (5.13-1.el7 as packaged by epel) with python 2
(Python 2.7.5 (default, Jun 20 2019, 20:27:34)
[GCC 4.8.5 20150623 (Red Hat 4.8.5-36)] on linux2).

Thank you!