ambiguousMegabytes property
Whether maxFileSize is one reading of a limit the store states without units, so a file just over it may still be accepted.
A field rather than a fact baked into the message, because the message is about this store's page: Apple writes "500MB" and means one of two numbers, and a second store's cap is its own business. Printed unconditionally it would tell a Play uploader that Google's limit is a reading of Apple's documentation.
Implementation
final bool ambiguousMegabytes;