Contact Birthday values Differ in Export on iOS vs Mac

I have a shortcut that is exporting name, birthday from Contacts to a text file. When I run the shortcut on my Mac the value matches the contact record, but on iOS the values written to file are contact birthday -1. Based on some things about how the DOB is stored in contact I believe it has to do with timezone offset that is stored with the contact record, but it seemed odd to me that it would work differently across different device types.

Below is the output from three runs on my three devices.

Steven’s iPad
Test Contact,2020-03-24

Steven’s MacBook Air
Test Contact,2020-03-25

Steven’s iPhone
Test Contact,2020-03-24

Link to Shortcut. I realize there are other ways to do this with dictionaries and such, but I’m experimenting.