The main objective of version 240 is to add new cataloging checks, and update some existing ones, to better accomodate the RDA/MARC records that are beginning to appear 'in the wild'.
This process is likely to continue for some time.
In version 240, we have added several hundred new cataloging checks, and almost all of them deal with 260, 264, 300 and 336-338.
We appreciate your feedback on how all of this works (or doesn't) on your end. If there is a problem, we will first try to supply you with as straightforward a solution as possible using the existing customization options; and then, of course, we will try to resolve the problem for the next version.
A complete list of changes between version 239 and version 240 is available here