Hi,
Acyba is complete rebuilding v5 from the ground up and that is v7. It's not just an update, it's a complete new piece of software.
As both versions use their own set of database tables you can install both on your site. You will be able to use both, but you can attach your licence only to one of them. Because of that the cron only triggers the one that has the license attached and the automatic sending also only works on the one with the attached license.
This way you can continue to use v5 and get familiar with v7. Once you're ready you can migrate your data from v5 to v7 and start production with v7 after you have unlinked your license from v5 and attached it to v7.
The migration process is explained here: https://docs.acymailing.com/setup/migration
Due to major changes in the software you would need to recreate your Smart newsletters as Automatic Campaigns in v7. And you need to recreate your subscription modules with the v7 ones, otherwise users keep getting subscribed to your v5.
All documentation can be found here: https://docs.acymailing.com