<Andy B wrote:
In the helper column use: =TEXT(A2,"dd-mmm-yy")
[....] copy the range and Edit|Paste Special|Values
to replace your formulas with the actual values.

Yes. Great! That does solve the problem I asked about.
Thanks.

But now I have a Catch-22. I need the dates to be treated
as text because I want to have gaps in the sequence --
adjacent cells that are not adjacent dates.

But when I select that column (after applying your
suggestion) as the X-axis for a chart, the X-axis labels
appear as ordinal numbers 1, 2, etc.

I wanted the cell context (dates) to appear as X-axis
labels. They appeared that way when the cell value was
interpreted as in "date" format. (Klunk!)

Can I have cake and eat it, too?