Roll with Castelli sent my rider on different route

Join the ‘Roll with Castelli’ route today but was one minute. It put me behind the main group with some other rides which no problem, thought we could then work up to main group.
Came to a junction they went left i went straight on and up zwift kom. It did each time i came to that junction so i could never catch up the main group or finish the event. Rode the distance but still no event finish.
I couldnt turn around or pick which turn to take!
Why and how does it do this?

Hi @Chris_Dutton4325 welcome to Zwift forums

It’s not clear from this partial sentence - did you mean to say you joined the event one minute late? If you didn’t start in the pen with the other riders in this event, it’s possible that late join was not enabled for this event, which would explain why you were steered on a different course.

Yeah I did join a minute after the start.
It did say late joining was fine.