тут пишут, что не нужна
http://www.iatatravelcentre.com/

Nationals of Russian Fed. with a common format residence permit issued by Cyprus can transit airside without a visa through London Heathrow on the same calendar day.

от какой даты?

в этом документе и написано:

Nationals of the countries shown in RED (underlined) above need a visa to transit
AIRSIDE unless they hold one of the following:
(iv) a valid common format residence permit issued by an EEA state or Switzerland;