How hard is EBC trek and flyback by helicopter?

EBC trek and fly back by helicopter, as the name suggests, is a wonderful trek up to the base camp of the world’s highest mountain where trekkers need to walk one way up. After reaching the base camp, hikers need not walk back down rather will fly back on a thrilling helicopter ride, either to Lukla or Kathmandu, based on their demands. Normally EBC trek is a moderate or demanding trek which does not require any technical expertise of mountaineering. It is basically a long hike up to an altitude of 5,364m (17,599ft.) and it seems difficult only because you need to walk for 7 to 9 days all the way up to the base camp on varied terrains.