29 April 1958
Many of you know that the Telexpo is in fact the building which represented the Belgian Post plus the Telecommunications which was represented by MBLE. The Telexpo building was also represented in the highest value stamp of the Belgian set.
The Telexpo building was interesting in terms of the Belgian Post. In the building itself, you were able to look at the history of the stamps and the museum of Belgian stamps. See also plan hereafter.
What you were also able to see was the life printing of the Belgian stamp set in front of the public.
Together with the printing of this stamp set, there was a specific cancellation which is known as the Telexpo cancellation.
Personally, I think that the first date of issue of the Telexpo cancellation is the 29 April 1958, which probably also was the date that the first stamps were printed in front of the public. This is however pure HYPOTHETIC, if there is anybody that can help me with this mystery, please contact me.
The telexpo cancellation is the cancellation which you will find dated with all possible dates u to the last day of the Expo 58. Mostly the cancellation can be found on all 6 stamps on cover. As a complete paradox, the only cover with the first day cancellation of the Telexpo cancellation is the rarest to be found in the range of the Expo 58 covers (Campo Rodan).
The official Expo 58 cover (R). The used cancellation is type 1: font for BRUXELLES - BRUSSEL is larger and you have a dash before and after these.
Official card with the date cancellation of 13 October 1958. The used cancellation is type 2: smaller letters for BRUXELLES - BRUSSEL and there is a dot before and after these.
Final note: there is also a Telexpo Congres cancellation, I will add this one later on.