Date difference is incorrect when moving between dates

[hyperjeff]

Neat time tool! A hopefully helpful bug report: When launching tz, it will correctly note a date difference (or lack thereof) between different time zones, but when you use arrow keys to move to other times, it will still maintain the date difference established on launch for all other times, even when it should change. See video, which compares US/Central to US/Eastern time zones. Comparing with US/Pacific shows correctly that there is not currently a date difference, but then continues to claim there is never a date difference at any hour.

https://user-images.githubusercontent.com/64038/226516850-e9940b8f-00b4-40fe-a0a3-eea5c8fc7afc.mov