The communications and "chatter" - uncovered by British intelligence only after the Russian passenger jet tragedy - are what led David Cameron to say it was "more likely than not" that a bomb brought the plane down on Saturday killing 224 people.
The intelligence resulted in Britain suspending all flights to and from Sharm el-Sheikh, leaving 20,000 British tourists stranded at the holiday resort.
Flights will resume on Friday with 20 aircraft carrying about 4,000 people back to Britain. But passengers were warned they would not be allowed to take luggage in the hold.
The move suggests officials fear a bomb was smuggled into the hold of flight 7K9268 in the checked luggage. It came as it emerged Britain raised concerns around baggage handling at Sharm el-Sheikh airport ten months ago.