Welcome to FT
Intrepidrobin and the BA Board.
I'm sure our BA Ambassador,
corporate-wage-slave will be along to officially welcome you and who has a tremendous amount of knowledge regarding BA and flying in general.
Assuming you mean August 2015

it is well worth a look here to get yourself familiarised with the workings of BA etc.
http://www.flyertalk.com/forum/british-airways-executive-club/1540695-your-guide-spending-avios-2014-a.html
Redemption seats in F to the UK will cost 150,000 miles. Business class will be 100,000 and thats just a general rule. They open up 355 days beforehand
however this is no gaurantee that any will actually appear at all.
On the Chicken and Egg title they can be as rare as Hens Teeth nowadays to find from SFO, LAX etc and bear in mind YVR flies the old F cabin which is now sold as Club World.