I'm actually not going to make any assumptions or theory crafting based on one very ambiguous piece of artwork/screenshot, as the last time SE put a patch story plot reference in a patch title logo before the patch was actually released, no one picked up on exactly what it was or what it actually referred to (the chalice in the title for 'Before the Fall' being of course
Nanamo's poisoned wine glass during her 'assassination'.)
Personally I think this will have a very mundane explanation which will just disappoint players who thought up more outlandish theories so I'm just going to sit back and wait and see where this story takes us. Either way, I really don't buy these bizarre 'Minfilia is Hydaelyn/Hydaelyn is evil' theories.