Spoiler via Memory Fraction

I just arrived in the Domain of Kourna and started exploring the Allied Encampment. Upon collecting a thing in the sky however, a cut-scene started playing. An amazing cut-scene to be fair, but apparently it was a cut-scene to a story mission I should not have been able to experience just yet. On the wiki I read that these are only meant to be accessed via Skyscale, but a my glider worked as well!

Spoilers are not fun, so please don't make the memory fractions appear before having completed the story missions.

Thanks!