Question about testing vB4 while keeping vB3 in open

[tthmods]

We are currently running 3.8.4 and need to purchase the license for vB4. We intend to test vB4 on a test forum before implementing, since we are aware of modifications and custom written mods breaking.

That being said, can we purchase the vB4 license and utilize it in our test forum and still be able to download updates as needed for vB3 for our open forum? I've tried reading through the threads and don't seem to be able to find where it was addressed.

Our main concern is if we buy vB4 that we will no longer be able to get updates for vB3.

Any assistance you can provide would be greatly appreciated.