This message is a from a CIA group resident in the Russian embassy, sent back to headquarters. Therefore, it is likely that it begins with "to headquarters:"
WARNING: This cryptogram contains at least one "fixed point". These are letters of plaintext that encrypt to themselves as ciphertext. (For example, J encrypts as J, or something like that.)
Strength of Hint: 631 out of 1000
Good luck!
A joint project of Brendan Bard, Prof. Gregory Bard, and Prof. Seth Dutter, University of Wisconsin---Stout (January 30th, 2019)