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MailStream Plus - How many Periodical automation flats pieces does it take to make a bundle and a sack?

MailStream Plus™, all versions, all platforms
The USPS Domestic Mail Manual gives the presort regulations.  It can be found at pe.usps.gov.
Section 207 25.0 is the preparation instructions for Periodical Auto Flats.  

Although there are exceptions given, the general rules are:
For Bundles section 25.3 says the minimum is 6 pieces to a destination in order to make a bundle, until you get down to the Origin Mixed ADC or Mixed ADC levels.
For Sacks section 25.4 says the minimum is 24 pieces to a destination in order to make a sack, until you get down to the Origin SCF, or the Origin mixed ADC or Mixed ADC levels.

(The DMM references above are as of April 2019.)
UPDATED:  May 15, 2019