I can definitely replicate this. Let me try to pin down the issue and I will let you know once a fix has been made.
Thanks for the detailed report!
Update: Found it and will be pushing this fix out soon.
Update 2: I found a bug in OSPi I will have to report. The start day byte, days0, is slightly off. Ticket has been submitted here: https://github.com/Dan-in-CA/OSPi/issues/21