I heard from here at least that the release date for episodes 555-574 english dubbed will be released on March 20th for one piece. What the frick is going on. Unless someone's info. Was wrong. The episodes should be up.
according to both Wikipedia and Rightstuff the DVD Release of the 4th part of Season 9 (Season 9, Fourth Voyage which covers Episodes 553-563) is the 20th of March 2018 and as of writing this (21/03/2018 GMT+10/11) it is in stock (as opposed to pre-order) as such the information is correct if it was talking about DVD release
for the rest (564-574), Part 5/Fifth Voyage isn't expected to be out until the 15th of May and still only a Pre-order on Right Stuff
this is further backed up by English Dubbed Anime Lovers
The episodes should be up.
if by this you are referring to Streaming i can't check Funimation as Geoblocking prevents Australians from viewing the page however as it is Funimation who releases the dubbed DVDs it's likely they have it up there already (since the DVD is out for 553-563)