Sometimes I clone a route to tinker with it, that creates a new KUID number for the clone. Sessions are affected if a route is deleted, since the route itself is a dependency of the session. The reverse is not true, the route can exist with no sessions at all, if you delete a session it doesn't affect the route at all. I have done weird stuff like;
1. Clone route and experiment, decide I like the experiment better than the original.
2. Edit cloned route in content manager, copy the whole folder and paste to a temp folder.
3. Edit original route and open config.txt, copy the KUID number and paste into the temp folder config.txt to overwrite.
4. Delete clone from content manager.
5. Copy all files from clone in temp folder, paste into original route editing folder to overwrite all files.
6. Edit, commit, now the experimental clone has replaced the original which still has the originals KUID number.
That process overwrites one route with another and keeps all the sessions working.
To make a session work in a clone is easier, edit that in Explorer and open the config.txt;
kind                                    "profile"
kuid                                    <kuid:522774:101363>
username                                "American Flyer 1100"
description                             "Switching activity for American Flyer route, free style template. 10 minute AI traffic from both ends plus 30 minute AI coal drags with different routes to follow. Similar to template 1 but with coal drag spawning reduced to 30 minutes so less traffic jams."
map-kuid                                <kuid:522774:101319>
category-class                          "YP"
category-region                         "US"
category-era                            "1800s"
trainz-build                            3.3
Replace the map-kuid with the one from the clone, now that session is transferred to the clone.