Now that the timezones match, resetting the due dates on the iPad should correct them on all platforms after you sync.
For example, on the iPad, you could use multi-edit to select all your tasks due today, then tap More > Edit Due Date. "Today" should be selected by default, so you can just tap Done. This will initiate a sync and reset the due dates for all the selected tasks.
Hope this helps!
Posted 7 months ago