The European Trading Post has already rolled over to May, and to our surprise, it's offering different items than those advertised by Blizzard last week! It's unclear if this change is intentional, but would appear to be a mistake, as all three of the new items on offer have broken models.
Update: It appears that the Trading Post has been temporarily taken offline! Whether this means Blizzard is fixing the broken models or replacing them with the originally announced offerings remains to be seen.From the preview post, five items appear to be missing from the May Trading Post. It also appears that Tiercel's Wing is a cosmetic warglaive, and not a sword as stated in Blizzard's preview.
High Priestess's Ceremonial Drape Ensemble: Wanderer's Snowy Trappings Ensemble: Vagabond's Snowy Threads Crimson Bicorne Merciless Trapper's StaffWhile the Medivh hood, staff, and cloak transmogs we datamined in February have been added in their place, though all of them appear to still be encrypted, resulting in broken models!
Feathered Cowl of the Guardian Standard of the Guardian Feathered Drape of the GuardianWe expect this issue should be corrected sometime tomorrow morning during normal working hours.
Read more on wowhead.com