It seems I made a mistake before :(
I pushed a tag to my repository without pushing the corresponding commit. Therefore, the addon's version didn't get updated in the addon.xml file.
I've bumped the version and made sure the commit/tag are there this time.
*addon - plugin.video.academicearth
*version - 1.3.1
*tag - 1.3.1
*xbmc version - eden
Sorry for the hassle.