I just had a user who installed Traveler on his phone. He previously had mNotes on his phone so he already had Calendar Entries on it. Anyways after he setup Traveler he now has 3-4 entries for every calendar event in his mail file. Traveler did tell him that his Calendar data would be replaced on his phone.
You will need to open a PMR to get to the bottom of this one. Traveler replacing calendar entries has been tested quite a bit, but it’s always still possible that something went wrong with some unforeseen mNotes issue. But that would only explain 2 copies of the entries - not 3 or 4. The PMR would need the Traveler client logs from this time, so if it has been too long since then, there isn’t much to do other than disconnect the device from Traveler, clean up the calendar on a PC (so that the mail file is correct), do a Tools - Replace Data on Traveler (and turn it back on).