Hi Renee, Registering a few days before the brevet is recommended -  brevet registrations appear in the Membership section of the website and other members can see who’s riding then. You can always edit the registration or cancel it. On that note, yes you can change the date you’re riding as per the previous Google chat - no reason is required. 
As per Eric’s comments on the directions, I’ll take a look at that but it will be next week as I’m travelling this week. 
Hope you have a great ride at the weekend!
Cheers,
Matt