Two views of Clervaux are found on the 40c Second Series of Postal Stationery Viewcards!

Have you noticed? 

The Clervaux view
was redrawn in 1931!

LHBK 97-01a --- Prifix 102

21 Jul 1930 Printing

LHBK 97-01b --- Prifix 102

 

1931 Printing (redrawn view)

 Mersch

11 Jul 1931

to

Bruxelles, Belgium

The other 11 views in the 1931 printing were not redrawn.  Why was the Clervaux substantially redrawn?  

Also, on the 1931 printing of the 40c Clervaux view the stamp imprint appears in a deeper green than it does on the 1930 printing, and the view is printed in a deep reddish-brown, whereas the 1930 printing is in brown.

The two different Clervaux views are listed in the Luxembourg Handbook.