Why do I have several downloadable gradle distributions (same version)?

Question

I look around in my ~/.gradle (moved to P:\caches\gradle , which does not affect this behavior), and I found some strange folders.

In the past, I upgraded several projects from 2.0 to 2.1 by running gradle wrapper , updating project\gradle\wrapper\gradle-wrapper.properties

I just found out that for some reason the same distributionUrl zip file was downloaded several times. As you can see, they all have the same size, and I made binary diff, they are the same in bits, except for timestamps:

The contents of each folder above are as follows:

I just upgraded from 2.2 to 2.2.1 and it happened again: this time these are 2 folders not 3. Does anyone know why this is happening?

I use Gradle from both IntelliJ Idea and the command line.