It’s becoming increasingly clear that everyone (the Americans, the British, the Iranians, and likely the Russians) knew about the likelihood of an attack in Moscow. Makes it even more odd that everyone’s intelligence was right on everything except the date.
The Iranians knew that an attack was brewing. The Americans and British knew the date (March 7th, within 48 hours) and a likely target (“concerts”, as described in the US Embassy notice). The Russians had even pinpointed the location (Crocus City Hall, which saw a massive surge in security presence on March 7th and in the days following).
Why, then, did the attack occur on March 22nd? Did someone tip off the terrorists that their operation had been compromised by foreign intelligence, forcing them to call the original operation off and reschedule?