Can I change the Creation Date (and Time) of an existing Waypoint?

Hi, I'm trying to take some Routes that I created in January 2018 and update the Creation Date of the waypoints in them to be accurate with the date and times of photos I took at those waypoints when I was actually there. Is there a way to do this? When I get done, I'm hoping to use the .gpx Route file to upload the GPS Coordinates into a large set of pictures I took on the trip using exiftool. I know if I have a.gpx file with correct dates and times that correspond to the images, it will interpolate and put in GPS coordinates. Can anyone help me understand if it is possible using Basecamp or some other software to change the Creation Date of existing Waypoints? Thanks!