Chief executive Michael Lewis has called for government intervention to help struggling households.
Freya Lewis, who survived the arena bombing, is among those taking part in the Great Manchester Run.
Those expected to be identified in the report on No 10 gatherings have until Sunday afternoon to respond.
Democrat Congressman Richard Neal is leading a congressional delegation to the UK and Ireland.
YouTuber, Max Fosh, says the "prank" is to put smiles on faces and is sorry for any confusion caused.