Conversation so far:
When did Tom Simpson move to Brittany?
In April 1959.
Why did he move to Brittany?
his National Service papers were delivered; although willing to serve before his move.
What did he do once he moved?
He applied to local cycling clubs, and joined Club Olympique Briochin, racing with an independent (semi-professional) licence.

Question: How long did he race in Club Olympique?
Self-contained rewrite: How long did Tom Simpson race in Club Olympique?