France: Air France 2 booklets of airmail labels

Here are 2 airmail labels booklets issued by AIR FRANCE. Booklets have 2 vertical strips of 5 airmail labels.
Both booklets released in 1936. First in April and second in May. Some booklets issued in April come with
imperforated strips. What is interesting in my booklet that one strip is perforated and another one not.

Year: 1.4.1936, Ungummed. Günter Mair's catalogue no: - FRA-B-77a, perforated H 11, blue/white, 2**

Year: 1.5.1936, Ungummed. Günter Mair's catalogue no: - FRA-B-77b, perforated H 12 ½ , 
dark blue/white, 2**