Plans for CIS-2018.

50% prepayment by the end of March.

I don't understand this point. Who will be making the prepayment? If it's planned to collect from everyone who might want to go, I'm afraid this option is doomed.

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Albert, which two options in Moscow have already been ruled out due to bookings for May?

Maybe Korolev is booked for a Clash of Heroes tournament? :D