Broken record-update behaviour in SRFI-57

Questions & Answers
1

I'm trying to use SRFI 57 (the extended record types). According to the documentation, SRFI 57 is supported and indeed it appears to be built in to Racket. This is with #lang racket and (require srfi/57) as preamble.

SRFI 57 provides functional updates. The following works in the REPL (an MWE I pulled from the SRFI document proper):

(define-record-type point (make-point x y) point?
  (x get-x set-x!)
  (y get-y set-y!))
                 
(define p (make-point 1 2))

Now, if I declare that in the REPL, I can do the following just fine:

(record-update p point (x 7))

But if I define the first portion in a racket source document, use enter! and try my record-update command in the REPL on the record instance p, I get an error like so:

cdr: contract violation
  expected: pair?
  given: #f
 [,bt for context]

What I don't understand is what the difference could possibly be. It seems like a bug to me. point? holds for this p object in the REPL, so it isn't like how struct types when redefined don't refer to the same object as older objects defined as one.