VERIFIED SOLUTION i

New May 31, 2015 postage rates in the MailStream Plus 8.2.0 and 8.2.1 May Postal Reference Files

No, the presort rate category structure is changed and so it wouldn't work trying to make the new rates fit into the old software versions.

(FYI- MailStream Plus 8.3.0 should be used for all mailings entering the USPS starting May 31 and after.  Also, the May files will be the last ones released for 8.2.0 and 8.2.1)
UPDATED:  April 12, 2017