I wasn't able to get the upgrade to work. Because of critical nature of our data and login method, we spun up a new server, installed Gluu 2.4.4 and manually transferred our data. We had little data at the time so it wasn't too painful. We had to use a different Client ID and secret for the OpenIdConnect auth method we were using. A side benefit was that I could move to Ubuntu 16.04 from the 14.04 we had been using previously.
I also didn't have the time to try to figure out my own LDAP export and import.
Going forward, though, an working upgrade path will be required. So, I will either spend more time to make sure its working or develop my own upgrade path.