That log shows start of stream, nothing for 15 min then end stream ??
All the normal stats for stream/recording are missing (rendered frames, etc) ??
Looks odd to me, sorry I don't know enough to troubleshoot further. But I'd start with basic, full reboot, making sure unnecessary background processes NOT running, no change in any security software that could impact OBS, and try a test stream again and see if you can get a normal OBS log.
And you might want to research what OS and driver updates took place recently on your system