Reflex

[pars]

Dear everybody!
What is the exact meaning of "Reflex" in the following passage? It is from the book “Persian Gulf Command” by Ashley Jackson, p. 261. Churchill's proposal was for appointing commanders in the Middle East. Of course, the meaning of "reflex" is clear, but, I think it has a different meaning here.

Having secured Brooke’s support, as well as that of Smuts and Resident Minister Casey, Churchill sent his proposal to the War Cabinet, which immediately met to consider this far- reaching telegram, Reflex no. 35.

Many thanks in advance.

 

[emsr2d2]

There appear to have been at least two initialisms/acronyms used to refer to telegrams. They appear to be code names used to refer to specific senders.

If you look at this document, you'll see that they refer to "a telegram from the Prime Minister (REFLEX No. 35)" and "the telegram sent earlier in the day by the Deputy Prime Minister (TULIP No. 45)".

This document uses "REFLEX No. ..." with different numbers.