Redent refers to someone who, after discovering their sexual or gender identity, changed their identity later on for some reason. This could be because their feelings changed, they found a more appropriate label, had originally mislabelled themselves, or something else.
This term does not apply to those who were assumed to be cis or straight and then realised they weren't, but rather, people who questioned their identity, discovered who they were, and later changed their minds. This also wouldn't apply to those who discovered their identity, and then discovered another part (such as a bisexual person later discovering they were trans), but when the identity is changed to something else (such as a bisexual person later realising that they were actually pansexual instead). The new identity can be merged with redent, such as a redent-bisexual, or used as an identity on its own, which may be preferable for those who have changed multiple parts of their identity.
The flag can be mixed with the flag of the identity it applies to by adding a stripe of the redent flag to the appropriate pride flag.
An important note is that this term does not imply that people have a choice of their identity or choose to change it, but rather that it can be difficult to understand your own emotions and how you identify, and that nobody should feel ashamed if they realise they are a different identity to what they originally thought. Nobody should be mocked for getting their identity "wrong" and needing to change it to something that better describes them.