Opening SB pro 5 files on SB pro 4.1 ??

I just upgraded to SB pro 5 as part of a the silver membership promotion. One comment I was reading on a different thread is that version 5 files cannot open on version 4.1.
This is somehow concerning since this hasn’t been clearly stated before the upgraded as the promotional people on toonboom is somehow " pressuring " you for the upgrade.
Now, the studio I am working for most likely won’t upgrade to version 5 because the reality is, the changes between versions are not that big… so what to do now. is my client forced to upgrade to version 5? if they don’t then how do we solve this issue?
Thank you and it’ll be very helpful if someone can shed some light on this.

As you have written, version 5 files cannot be opened in version 4.1. If you meant something else when you wrote “version 5 files cannot open on version 4.1” please clarify.

By definition, things are changed and added to an upgrade of software.

It is considered common knowledge that an earlier version is not equipped to understand a future version of software.

Sometimes, frequently even, the reverse is possible and you can open files created with an older version in a newer version of software however it all depends on the specific changes in the newer version.

As for your dilemma contact Sales and see if you can revert back to an older version.