Red Rocks gravel cycling day trip

Hello this description will be updated with more logistics when I get the next highly anticipated burst of energy. 

However, the plot is as follows: 

On Sundays, the Red Rocks Coastal Road is closed to motorised vehicles, allowing uninterrupted pedestrian access. (IDK maaaaybe there will be one or two vehicles from people who own the batches around there ? not sure how that works).

I want to ride my bicycle, I want to ride it where I like, and on the 9th of November, that’s from Red Rocks all the way to Oteranga Bay, where the high voltage cables make landfall from the South Island. Stopping for food and returning in reverse. 

I gues-timate a moving time of 2.5hours each way. Please don't hold me to that. plan to spend the whole day taking in the scenery and yapping. 

You should expect cycling over a mostly gravel/loose gravel 4wd track, with minimal elevation change, and a small amount of sandy / very loose gravel sections where you'd probably walk over.  

The tide forecast for this day (9th of November) is:
High tide - 5:32am (1.6m)
Low tide - 11:53am (0.7m)
& High tide again:  5:56pm (1.6m)

So we shouldn't need to worry about getting our toes wet if there happens to be a very coastal section to this coastal track.