If you see two X's in his lacing, the package is at the alternate drop site.
If he has 3 X patterns, you're burned! Make your way to the safehouse after losing any potential tails.
Glance quickly, agent, and keep moving.
> Every Tuesday, shortly after 7:00, a British MI6 officer would take a morning stroll at the Kutuzovsky Prospekt in Moscow. He would pass outside a designated bakery at exactly 7:24 a.m. local time. If he saw Gordievsky standing outside the bakery holding a grocery bag, it meant that the double agent was requesting to be exfiltrated as a matter of urgency. Gordievsky would then have to wait outside the bakery until a second MI6 officer appeared, carrying a bag from the Harrods luxury department store in London. The man would also be carrying a Mars bar (a popular British candy bar) and would bite into it while passing right in front of Gordievsky. That would be a message to him that his request to be exfiltrated had been received.
There's a great book that covers every single aspect of this escape, "The Spy and the Traitor" by Ben Macintyre. Rest assured that the British embassy had plenty of Mars bars and Harrods bags for this signal!