How do you use the Implicit Context Load option, under Project settings, to manage contexts in routes?
The Implicit Context Load feature is used in Data Integration (DI) Jobs, not routes. Routes use the routeName.cfg file.
For example, you have a route called myRoute, with some context variables:
Any other context name not specified in the file, the value used is the one you specified in the route.
Note: if you deploy from TAC, this file is created automatically, and you can edit it after TAC deployment.