Auth Token Type has changed & how long is the new token valid

Hello, the documentation says the auth token is bearer type, but is has changed.

I used the bearer token to read exp timestamp and request a new token only if the present unused token is expired.

Because this is not possible anymore, i need to know how log the new token is valid. the old token was 24 hours valid.

It would be nice if changes of this kind were also announced.

Best Regard

Enrico