Hi folks, quick update here: we expect a read API for time tracking to be available by the end of January – we’ve updated the original post to reflect this.
To further clarify: as @Stefano_Tranquillini mentioned above, Estimated time works as a numeric custom field that you can read and write, with the value representing a duration in minutes. Actual time will be a new property on task objects available for reads but not writes (until later in 2023).
We’ll let you know when the API is available via the forum and update the our API documentation with the details. Apologies once again for the confusion.