It is not Wiki misinformation it is from the official diamond jubilee website
The Queen acceded to the throne on 6 February 1952 on the death of her father, King George VI.
http://www.thediamondjubilee.org/accession
Proclamation of her accession was 6 Feb was recorded in the London Gazette. The Accession Council took place on 8 Feb followed by formal proclamation read out in various places - I am old enough to remember this happening.
It still doesn't alter the fact that her accession happened on 6 Feb on the death of her father.