I've been in campaigns that lasted for several years that ended with absolutely no warning at all. When a good campaign ends the market will be flooded with its participants looking to join another and will likely be picked over other users.
If your campaign dying will screw your finances then you should be planning for that. It could happen any moment. I've seen people saying their pay their rent with sig campaign payments. That's nuts.
Exactly. I experienced such thing myself. I joined BitBlender campaign, in early of 2019, but in fact that campaign lasted for years. The Bitblender platform used to be one of the oldest and most reputable mixer services, but suddenly the platform shut down with short announcement, and it is a scam exit. That is life, and every good campaign has to end someday.