I have encountered this many times in the past few days.
On the zone map, a heroic encounter shows up with xx minutes left. When you arrive at the location, the Heroic Encounter is not there at all. Also, I have found sync issues with two heroic encounters so far:
1) Protect the Merchants (Reclamation Rock) - The merchants show up on the map, but there are no enemies. Once the heroic encounter starts, you cannot complete it since there are no enemies to defeat.
2) Protect the Merchants (Drowned Shore) - Again, merchants appear on the map, but the Heroic Encounter will not start. Map displays that the heroic encounter is active.
3) Free the Sea Elf Slaves (Drowned Shore) - Either the enemies show up or the slaves show up. Not both at the same time. In any instance, you cannot complete the encounter.
It is almost as if the time sync is off from when the heroic symbol appears on the map to when the enemies and objective appear.
I have duplicated the Drowned Shore heroics several times. I am just now discovering the Reclamation Rock heroic encounter problems. Have not checked the Fiery Pit or Spinward Rise.
All zones for the Elemental Evil Campaign..
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