Garmin Livetrack or Strava Beacon

I am taking on a 114 mile ride this weekend for charity and want to post a link so that people can follow my progress. I know garmin livetrack and strava beacon do this but for those to be enabled you have to have started the ride. Is it possible to send a link out pre ride, say something i can post on social media etc ?

I share my long rides with my wife on google maps. It doesn’t show the route I am following but live location is helpful.

You can start Livetrack on your phone and send out links to email contacts or facebook.
The tracking doesn’t start until you start your Garmin device.
Not sure how far in advance you can start the Livetrack on your phone though.