thanks, I guess it's a flat course. Still, that is a good speed for 4th cats and too quick for me! If it was 24mph I'd have considered racing.
You adapt to the speed pretty quickly - give it a go!
If you get dropped, usually you can wait for them, jump back onto the back - rinse and repeat.
Next week...aim to get dropped a little later in the race, the week after a bit later, then hold on, then top 10, then top 3, then win

Everyone starts somewhere, usually with being dropped first time.
Get some anaerobic training in to prepare you for the big surges and you'll be good to go (1 minute intervals, 5 min rest is a good place to start)