VERIFIED SOLUTION i

"Bdls < QA may be created due to BL MAX weight" and "RS bdls < force may be created due to BL MAX weight" warnings in MailStream Plus Context Checker

Product affected: MailStream Plus™, all versions, all platforms.
For example with mailing Type- 
ML TYP 4 F B  (Package Services Flats Bound Printed Matter)

The trigger for getting those warnings is that MailStream Plus™ (MSP) checks to see if it will always be able to make a bundle with at least 10 pieces in it based on the Max piece weight in the mailing, and the BL MAX weight. 

The USPS rule is, for example in DMM 265 7.3.2, "minimum 10 pieces or 10 pounds" 

MSP checks the worse-case-  if there were 1 less piece than twice the 'Qualifying Amount' pieces to a destination, or one less piece than the twice the 'Bundle Force' amount to a destination, can it put them all into one bundle?  
Because if it can't, and has to split that quantity of mail, then one of the bundles is going to have less than the minimum number of pieces. (and the weight may also be less than 10 lbs.) 

The actual formulas used are:
For the warning "Bdls < QA may be created due to BL MAX weight"  
BL MAX > ((QUAMT PCS X 2) - 1) X MAX PID weight      Good/True- no warning, else give warning.

For the warning "RS bdls < force may be created due to BL MAX weight"  
BL MAX > ((PKFRC PCS X 2) -1) X MAX PID weight       Good/True- no warning, else give warning.

-In the first formula above, 'QUAMT PCS' (the 'QA" in the warning message) is the Qualifying Amount which defaults to 10 pieces.  
-In the second formula above, 'PKFRC PCS' (the 'force' in the warning message) is the bundle force amount which also defaults to 10 pieces.
-'BL MAX' is the maximum bundle weight allowed, either due to the MSP default value, or a user entering a value in BL MAX position 18-22. 
-'MAX PID weight' is the heaviest piece's weight on the P ATTR parameter(s) in the job.


So using the defaults of 10 pieces, MSP takes the heaviest P ATTR piece weight in the job, multiplies it by 19, then sees if it is less than the BL MAX weight.  If it is less than BL MAX weight, then MSP can put 19 pieces into a bundle, and no warnings occur.
If the calculated weight is more than BL MAX, then MSP would have to split the 19 pieces into two bundles, and so gives the warning(s). 

But the warnings are just to let the mailer know, so in case he sees a bundle with under 10 pieces in it, he'll know why from the warning.  
The USPS allows smaller bundles when needed, DMM 265 7.3.1b- 
"b. The physical size of each bundle for each specific presort destination may contain the exact bundle minimum, more pieces than the bundle minimum, or fewer pieces than the bundle minimum, depending on the size of the pieces in the mailing or the total quantity of the pieces to that destination. Price eligibility is not affected when a physical bundle contains fewer pieces than the minimum bundle size for the above reasons."
UPDATED:  May 15, 2019