VERIFIED SOLUTION i

We can't get the new MailStream Plus implemented before it is required

Usually if a site has a presort incorrectly presented to the USPS, there are penalties or the mailing can be rejected.  But also, the USPS works with mailers when the USPS implements changes with such a short time frame that mailers find it impossible to make the date to be implemented by.
 
The suggestion is to go directly to the USPS to work with them for an exception or an extension on upcoming mailings that you will not be able to run with the new rates and presort logic. 

Then when you have the newer updated version of MailStream Plus tested and ready to move into production, you can move forward with the updated version.

 
UPDATED:  March 23, 2017