Critical Mass has no leaders and no one is entitled to make any announcement on its behalf. If there ever is any, the correct response to such an announcement would be for people to ignore it and make up their own minds.

However there is a mailing list where reports are shared sometimes; this is where the following text comes from. (The picture comes from face book)

We left from Waterloo and went around the city, including, Trafalgar Square, Buckingham Palace, Hyde park as shown in the picture taken from face book

If you want a better report, posts yours to londoncriticalmass@riseup.net or to the list http://lists.riseup.net/www/info/cm-london