On Wed WoE: Geffen 4 takes the place of Payon 4, currently held by Hellstorm guild.
On Sat WoE: Aldebaran 4 takes the place of Prontera 4, currently held by Wine Brewing Society guild.
Please report any issues you see with the castle rotation. And as a catch-call "just in case", if the upcoming Wednesday and Saturday WoE reports any technical issue due to the castle transfer that will interrupt with WoE and require WoE to be skipped, then WoE will be skipped with no compensation/penalty for any guilds involved.
The next rotation is in Oct 2021, some time after the Oct 16 WoE but before Oct 20 WoE (exact date/time pending on GM availability to carry out the rotation.)