The upgrade is performed by Joomla!'s extensions installer class (JInstaller), part of your core Joomla! installation. The errors are produced by JInstaller, not Akeeba Backup and are non-catchable. As a result, I can not modify them. I am wondering, there is a huge red box above the update area explicitly saying to you that you must provide a Download ID in the component parameters. You can't have possibly missed it?
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!