Modifying a small amount of OSM data

I have entered a few trailhead parking areas (less than 60) into OSM over the last few months, and just realized that I had not included the elevation data, which is quite valuable in this context.

I have retrieved my data (Xapi) and am about to add the elevations, but before I do that I would like to know how I get this data back into the database. If I upload the modified file from josm, will the modified nodes overwrite the originals, or will I have duplicates?

Any further advice on this much appreciated :slight_smile:

This depends on how you add the new information to you downloaded data. Make shure you increase the version-number of every node. If you edited your data inside JOSM, you’re fine and the data will be replaced in OSM

But just for testing: Download 1 node from the API, add the elevation and upload the node with JOSM. Now check, if you find 1 or 2 nodes in OSM.