I know the elites had yellow race numbers. I then saw a guy with a white/yellow striped bib. When I asked him what the bib meant, he said he was a club runner, and putting down a time of sub 1:20 AND being a club runner would get one near the front.
That is true for great run events, which is what I was referring to above, but you have to prove that you have already run that time, not just say that you hope to.
1) it depends what club you join and what you hope to get out of it.
2) however regularly you like.
3) it depends on the club. Probably.
4) no. Except in certain races where if you are a club runner and have a qualifying time, you can start in a section for 'fast club runners'. If you are currently at 3:05 for a marathon and are a man, this probably doesn't apply to you.
Seren, I'd suspect she may not have thought she was in with a chance of a medal, so didn't think to position herself far enough forward - if the other woman was allowed to do so when running that much slower, it ought to have been possible.