These watches aren't my speciality, but if we look closely at some of the watches in the same family in a 1979 catalogue:

we see they too say "Ebauches Suisse" on the dial. Which is correct, because the movement is indeed a Swiss ebauche, thanks to it coming from Valjoux :) And then the watch was assembled in France, hence the other watches with "Made in France". They are all skirting round the issue that they can't put "Swiss", "Swiss made", "Made in Switzerland" etc because there is a fairly exacting requirement for a certain % of the content to be Swiss before they can do that and this series of watches doesn't reach that %.

The pretty similar 13-1 underneath however does have "Swiss made" on the dial. There was a discussion about this quite recently here: http://chronocentric.com/forums/heuer/index.cgi?page=1;md=read;id=37304

It's possible that someone took exception to "Ebauches suisse" as being too close to "Swiss made", as how many watch purchasers were aware of what an ebauche is and just saw the Swiss connection. I'd guess, and I am only guessing, that the "Ebauches suisse" dials came first and were replaced by the more unequivocal "Made in France" later on.