[Samba] Classic Upgrade from Samba 3 to Samba 4.2.1

[Mario Pio Russo]

Good Day All

I need a very quick clarification about this:

Attention! Please verify that your Samba AD DC was not set up using the
classic upgrade method. If the classic-upgrade was used, we highly
recommend to NOT upgrade to the new 4.2 release. The bug report contains
detailed information on this issue.

now my question is, is it safe to upgrade directly from Samba 3 to samba
4.2.1 using the classic upgrade?

thanks