Limit on number of viapoints?

Hi, I am relatively new to cycle.travel, but find it very useful and interesting.  Could you clarify if there is a limit to the number of viapoints which can be included in a route?  I've clicked the box to add them, but it seems to stop after the 20th viapoint.  This has been using the web site in both Google Chrome and Edge.

https://cycle.travel/map/journey/658168

Eg I wanted to plot my return to Stanley mill

Many thanks