It depends on the host's policy. In the peertube model, your server is responsible for hosting the video so unless it closes down there's no reason for it to be

It depends on the host's policy. In the peertube model, your server is responsible for hosting the video so unless it closes down there's no reason for it to be unavailable. This has interesting consequences because it means you should not trust a random service provider to host your videos, but rather find a dedicated community on a specific topic, or an existing network (such as a local non-profit host) which is sustainable. There is currently no incentives for seeding and that's a good thing. Seeding (replication) is achieved as a community-to-community service between consenting sysadmins/communities. So if people from kolektiva.media find conf.tube content/concept interesting, the admins can setup say 1TB (or unlimited quota) of replicated content from conf.tube, and both sources will be listed as webseeds when you watch the video on either instance.