Apparently, and known, these are random attacks.  Sign on at 7am DST U.S.  MC's attacked early morning.  Funds depleted.  On/Off during the day, no attacks.  Off for couple hours, sign back on, raids on MC's.  Is there a time period between raids?  Miss out on upgrading DE troops.  Evidently, players in Europe get 1st go at funds.  Interesting game, but can't spend 24/7 waiting for raids to upgrade troops.