It's many years since I raced.
Myself and a couple of my old team mates had the fanciful idea, last year, of taking part in Vets races (to race as a Vet you've to be over 35 years old) this season and doing Paris-Brest-Paris too.
I had always kept my hand in on the bike after I finished racing : and I average between 16 - 20mph.
I thought that I would be able to race at the least.
But try as hard as I can, my average speeds never exceeded that range (16-20mph).
My mates quickly gave up the idea of competing when they were struggling to hit 15mph (it's over 20 years since they got on a bike in anger).