I have an application that shows a spike of 8000 downloads on a certain day (normal number is 20-30). This is not accompanied with a spike on Installations(about 30-40), which is about average. What could have caused such excessive downloads without also having installations?
Excessive downloads?
Search the forum for "spike". See in particular: https://developer.apple.com/forums/thread/695036
It's important that you contact Apple and tell them that you find this suspicious.