The Urantia papers and Foreword
were printed in
1955.
They were studied before that
in
Dr. W.S. Sadler's home in Chicago.

Dr. Sadler & a small circle
dealt with
unknown processes
of delivering these babies to the world.
A larger "Forum,"
a rotating
group of Sadler's formulation and maintenance,
studied and
reviewed the Urantia revelations as they appeared,
most
apparently intrigued if not persuaded by the new teachings,...

...but
with at least one notable departing the
Forum,

admonishing that Sadler was
conducting the process
autocratically.
"533" also appears in
Comradely
Clusters
More about that "one notable" in
How Does Revelation Succeed?
Dr Wm S Sadler of
Urantia Book note
is not to be confused with
Bill Sadler the actor