How to interpret overlapping journalctl boots on Raspberry Pi OS Bookworm?

I need to know the hours of the reboots of a machine. The system used is Raspberry Pi OS Bookworm. However, I'm a bit confused about what I read... If I understand correctly, the first date will be the startup, and the second will be the shutdown. But in this case, I have multiple startups with conflicting information. Here's my output:

-9 78e891182c6e4686aec796bf8b69f7e3 Mon 2025-04-28 09:17:01 CEST Mon 2025-04-28 14:32:01 CEST
  -8 90301c02b7d9415b80109bc8cebe6d8f Mon 2025-04-28 14:17:01 CEST Mon 2025-04-28 16:15:01 CEST
  -7 d4a81802b6ff49f596858c72a912874b Mon 2025-04-28 15:17:01 CEST Mon 2025-04-28 15:17:01 CEST
  -6 cbbb35a537eb4abf94d34fed8a5591ab Mon 2025-04-28 15:17:01 CEST Mon 2025-04-28 16:19:01 CEST
  -5 4e6a8bb5edba49fbafed1cc600a63852 Mon 2025-04-28 16:18:01 CEST Mon 2025-04-28 16:21:01 CEST
  -4 3c7bb8dc1c4d4d1fa332faec48c14b92 Mon 2025-04-28 16:18:01 CEST Mon 2025-04-28 16:18:01 CEST
  -3 57da6dc6a9ef4621b7015cd96d74e54b Mon 2025-04-28 16:18:01 CEST Mon 2025-04-28 16:18:01 CEST
  -2 a78180d2c8844db484d6e380e88e93f5 Mon 2025-04-28 16:18:01 CEST Mon 2025-04-28 16:25:01 CEST
  -1 a27e260f7c724f8cbd3195f54e7e155c Mon 2025-04-28 16:18:01 CEST Mon 2025-04-28 16:29:01 CEST
   0 dc8a18268f83437ba40bbc9377c284dd Mon 2025-04-28 16:18:01 CEST Mon 2025-04-28 17:07:01 CEST

Entry -8 indicates a session from 14:17 to 16:15, but the following lines show reboots during this timespan. The same is true for entries from -5 to 0: they all show a boot at 16:18 but with different shutdown times. What exactly is happening here? Is this system boots or something else (like a user session)?