What are creation_time and timecode in 'ffmpeg -i <vid_name> -dump' command?

Question

The command 'ffmpeg -i GOPR0221.MP4 -dump' gave me the following,

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'GOPR0221.MP4':
  Metadata:
    major_brand     : mp41
    minor_version   : 538120216
    compatible_brands: mp41
    creation_time   : 2020-03-02T15:23:13.000000Z
    firmware        : HD4.01.05.00.00
  Duration: 00:03:58.78, start: 0.000000, bitrate: 45149 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuvj420p(pc, bt709), 1920x1080 [SAR 1:1 DAR 16:9], 44996 kb/s, 59.94 fps, 59.94 tbr, 60k tbn, 119.88 tbc (default)
    Metadata:
      creation_time   : 2020-03-02T15:23:13.000000Z
      handler_name    :     GoPro AVC
      encoder         : GoPro AVC encoder
      timecode        : 15:37:56:22

I am in London and I had synced the GOPRO internal clock to the local time. So, I believe that the 'creation_time' means the instant at which the recording started or the time corresponding to the first frame. Am I right? and what is timecode then?