Every year there is an Audax of sorts which goes around the island, usually there is a forum contingent - some of whom will go fixed. It's lumpy and there are a couple of reasonably long climbs, but if you go into it with a little fitness and a sensible gearing there is no reason why you can't do it fixed; plenty do. I did it fixed last year and it was a lot of fun.
Every year there is an Audax of sorts which goes around the island, usually there is a forum contingent - some of whom will go fixed. It's lumpy and there are a couple of reasonably long climbs, but if you go into it with a little fitness and a sensible gearing there is no reason why you can't do it fixed; plenty do. I did it fixed last year and it was a lot of fun.
https://www.lfgss.com/thread83135.html
https://www.lfgss.com/thread57462.html
https://www.lfgss.com/thread39103.html
etc.
Best of luck with your sponsorship efforts.