When using PBS printable postage and I will be dropping the book in a blue collection box after the time of day for collection from that box, do I use the current day's date or the next day's date?

LaVonne--

I think you can use either date.

From the PBS help files:

• • If you put it into a collection box after the last day's scheduled collection, then the package will be accepted with the previous day's date when the next collection happens on the next day.
• If you are into legalese, here are the USPS regulations on this ("indicia" = postmark):
  • Mailpieces bearing a complete date in the indicia must be deposited or presented on that date, except that pieces entered after the day's last scheduled collection from the post office or collection box may bear the actual date of entry or the date of the next scheduled collection from the post office or collection box. When authorized by USPS, presort mail accepted after midnight may bear the previous day's date. If the mailer knows that the mail is not to be deposited or presented on the date in the indicia, the mailer must use a date correction indicium under 4.4.1. (from DMM, 4.5.2 Mailing Date Accuracy and Mailing Periods)

I usually put the next days date when I know I'm going to put it in the blue box after pick up time. But I don't think it matters that much as long as the postage isn'tmore than a day old.  I know I have forgotten to change it a few times and had no problems.