All of my SharePoint Forms that are built with PowerApps that I am publishing today are currently having the same issue. Any date fields do not save back to the SharePoint List. Is anyone else having this issue?
I have an intermittent issue with a PowerApps form on a list that doesn't save check boxes, it appears to reset them to the default sometimes just before saving the form. I haven't found an answer to this yet and only seems to occur on first use.