Is it possible to create an Ionic v4 project with latest CLI?

I am new to Ionic, I have to develop an Ionic app at my work, and one of the requisites is that it must use Ionic-v4.
I see in the docs the options to create Ionic v1, v2 and v3 projects and the default one that I guess is v5, but not v4.

What’s the reason for requiring v4? The differences between v4 and v5 are relatively small, surely it’s better to use the latest version?