Can't upload private Support app

Hi Caroline! I took a look at your account to see what the issue might be and I found the problem. To upload private apps, you'll need to be on the Professional plan or above and your account is not there. However, since you are a developer using a sponsored account, you should be on a higher plan level than you are and have access to this functionality. To that end, I'm going to give your Zendesk instance a temporary boost to the Enterprise level and then open up a conversation with the relevant team here to get your account permanently set to the correct plan level. I'll add you and your account owner to that ticket that I create and I'll follow along, so if you have any further issues there, you can both drop me a line there.
 
For the time being you should be able to do this successfully, so let me know if this is now working for you. It's likely that you will also have to refresh your Zendesk instance to see any new features in the UI, however it should just automatically work in zcli now. Talk to you soon!

Yay, glad to hear that resolved it for you! I just created that ticket to get this permanently sorted out, so hopefully it'll be smooth sailing from here.