I agree with you Rein when you say " but from 1963 onwards several stamps with a combined photogravure like the
1963 Olympic Wintergames in Innsbruck"
But they were basically one colour engraved combined
with one or two colour photogravure, no truly multicolour
(4 colour process)photogravure.
when according to this article by the Austrian PTT
(Post Telephone Telegraph) the OeSD bought a 4 colour photogravure press.
Even though the article does not mention an exact date when this
4 colour photogravure press was installed, the 6 value Fruit defintives were issued on 25.11.1966.
Neither does it mention the press manufacturer.
Was it a Rembrandt?
A couple of months prior to that on 28.9.1966 the first really multicolour photogravure combined
with one colour engraving was issued.
Austrian National Library
Scott 773 - 776
Followed in 1967 by examples like this
So is it possible then that they were printed by one pass
of the old sheet-fed Koenig & Bauer
recess press and one pass through this new
(in 1966) 4 colour photogravure press ?