With Excel 2016, VBA will not activate an alternate worksheet when the Macro is associated with a worksheet

I have a Macro that is associated with my "Introduction" sheet. It is triggered by a cell change and then calls a second macro that manipulates another worksheet, "TimeInLibraryData". It's pretty simple:

Private Sub Worksheet_Change(ByVal Target As Range)

Sheets("TimeInLibraryData").Visible = True
Sheets("TimeInLibraryData").Activate

MsgBox "The name of the active sheet is " & ActiveSheet.Name

Call CreateTimeLine.CreateTimeLine1(1)

End Sub

Public Sub CreateTimeLine1(PickSingleLib As Long)

Sheets("TimeInLibraryData").Activate

MsgBox "The name of the active sheet is " & ActiveSheet.Name

End Sub

You can see I am outputting the Active Sheet name. The problem is that in both places shown, i see that the ActiveSheet is the "Introduction" sheet when it should be "TimeInLibraryData"

The application was written in Excel 2010 and i have just updated to Excel 2016 where the problem is seen.

Running in Excel 2016, if I access the CreateTimeLine1 macro during normal runtime, it works. I only see a problem when the Macro is called following a change to the "Introduction" worksheet.

I have created a cut down example in VBA 2016 and found that it works as expected. I also created the simple example in Excel 2010 and ran it in Excel 2016 which also worked.

So - I have a very perplexing situation tied to the running a set of Macros written in Excel/VBA 2010 that is not working correctly in Excel/VBA 2016