IMpb for parcels is getting incorrect or blank text in TADF string text location using MailStream Plus

Product affected: MailStream Plus™, all versions, all platforms
Note: Intelligent Mail barcodes (IMb) are for letters and flats mailings (and in some cases for Priority Mail.)  The USPS has a list of valid Service Type IDs (STID) for Letter/Flat mailings. 
But Parcels use Intelligent Mail package barcodes (IMpb), and the valid STIDs for those are in USPS Publication 199.
There are many different IMpb STIDs and different ones are valid for different types of parcel mailings. It is possible to choose a valid IMpb from Publication 199, but have that value not apply to your mailing.  This can result in the IMpb text string having information invalid for your mailing, or even no text information.
Also, if MailStream Plus is not validating the STIDs (see below), the STID value may not be in Pub 199, and therefore no Banner text will be found to be used.

You can use the ALG PP position 10 to tell MailStream Plus to validate the value.  The valid values for IMpb are:

Y   Verify the STID - Validation is based on Class and Type of Mail
Note: For Package Services Mail (Non-Bound Printed Matter) both Media Mail (BS) and Library Rate (BL) Service type codes will be treated as Valid. 

N      Generate Intelligent Mail® barcode, not IM® package barcode; valid only for               Priority Mail

X      Do not Verify the STID's.  Use the assigned STIDs without changing them.

blank  defaults to X

So if you have ALG PP with position 10 blank (or the job does not have an ALG PP parameter), the default value is X and no STID validation will be done.  You may want to have the parameter there with a Y value so MailStream Plus will validate the STID being used.

All MailStream Plus parameters and their options are discussed in the MailStream Plus Guide.
UPDATED:  May 23, 2019