Only from the Start?

Hi,

Apologies if this has been raised before.  

I seem to have an issue where by if I don't start the guidance as I begin a ride and decide to load the course when I'm say, 10 miles into the ride the course isn't able to catch up.  The screen of my Garmin 520 Plus will only display the first guidance instruction and won't progress to where I actually am.  Is there any way around this?  Or is it simply that I must start guidance as I begin my ride?

Other than that I rather like cycle.travel, so simple to create a route...