[ENDWALKER MSQ SPOILERS] Timeline weirdness

[Jandor]

They mean the first as in the world we visit in Shadowbringers, some people think that is a different timeline to the source, where eorzea, othard ilsabard and others are located.

lol yeah I might have jumped the gun a tad.

That said though, honestly, it kind of is a different timeline. They were both one world with one version of events happening in the past, an event happened and they were split, they've since diverged down different paths.

The only real difference between a timeline and a shard is that a timeline in most fiction is more all-encompassing in scale, while the shards are implied to be a local space-time phenomena.