lonelornfr

I believe i found it at the very north of the durgan battery map (the outside map). You fight a bunch of knights and one of them drops it.

Without spoiling too much, i can say one of them is available fairly soon (level 5ish) and the other a bit later (i'd say level 7ish).

I was in the exact same situation as you. Going to the Woedica temple (copper lane) and attending the leaden key reunion there triggered it. I got a message saying that there was a letter for me at Caed Nua right after it.

I feel like i'm missing something obvious since i couldnt find any other topics on the subject but how do you go to the expansion ? My undestanding is that it would become available once you reached Caed Nua, but going there didnt do anything for me. So now i'm in copperlane, doing the sidequests there, i'm level 5 and still no sign of the white march. What am i missing ? Do i need a higher level ? Do i need to advance the main plot a bit more (i still havent gone to the temple of Woedica) ? Help please...