How to use nukes outside of the event using the CDK?

I’ve seen it a few times where people have been able to use the CDK to use the nukes outside of the event and I am wondering how it’s possible?

There’s a post here where someone was able to drop a 100 megaton bomb in a custom game using the CDK.

https://www.reddit.com/r/Warthunder/s/6ogp0bvZgY

So I’m just wondering how is it possible?