How many weeks do we need to keep doing the Nier weekly quest?

[Ultimatecalibur]

People keep saying about reward, but wouldn't people already know if any exists via data mining? I thought I read about the next exp buff gear, for example.

Different things are patched in at different times. The preorder exp buff gear, mount and minion are likely already in game to insure that preorder rewards are deliverable even if 5.55 and 5.58 end up delayed. They likely also included the next two seasonal events to avoid what happened last year even though they should occur after 5.55 and 5.58 are released.

If they are planning to add a Yorha trial they might be delaying it to release with 5.55 or 5.58.