Got this
e-mail today:
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Mom, it's your month.
Enjoy a book on us!
Get a copy of
Summer at Willow Lake by Susan Wiggs
when you register a new device or
Reader App until May 14th.
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Looks like it may just be physical devices and Android and iPhone apps (not sure about Reader for PC). Fine print says a limited number and that they will email you a code by the 16th.