Popping this here - my comment on Ryan ‘Free the Rear Hyrdation’ petition (thread).
This is the case.
Pros received this direction for Hamburg this (Thursday) afternoon (22nd May).
"UPDATED FAIRINGS
"World Triathlon, in consultation with its Technical Committee, the DTU, and the bicycling manufacturers’ industry has updated their Rules pertaining to fairings and Hydration Systems.
"Please review the following link:
“Alignment with this Rule at IRONMAN/ IRONMAN 70.3 events, will be effective starting on May 25th.”