It’s easy to check whether your multisite will work on Pressable.

First, go to My Sites -> Network Admin -> Sites in the top-left menu.

Here, you will see your site and subsites.

If your sites begin with the same domain but end differently (with a different directory), you have a subdirectory multisite.
And yes, it will work on Pressable!

However, if your sites all begin differently and end with your domain, you have a subdomain install.
This configuration is not currently supported by Pressable.

If you want Pressable to help migrate your multisite, please be sure to let us know!