I have seen nothing official that would confirm that the firmware in any of the cams has been changed to reduce the length of video uploads.
As @Omgitstony has indicated, once the cam triggers a Motion Event upload, the cam should theoretically continue to record and upload that motion event until all motion within the Included DZ or frame drops below a specific motion threshold for a specific time. The wildcards here are the “specific threshold” and “specific time”.
Since the user has no settings to determine how long the specific time period is for the cam to wait to see if the motion will continue, Wyze could theoretically set this value to 0ms which would cut off the Event upload at the very slightest millisecond pause in motion which would create many back to back short videos. I have never seen what this firmware set time is.
Since the cams record in daylight at 20fps and at night at 15fps, I would assume that there is a sperate time set for each and checked for pixelation changes between frames. If this is the case, the minimum frame by frame time would be 50ms and 66.6ms. If Wyze is setting the cutoff by a lack of motion from one frame to the next, again, lots of short videos for momentary pauses in motion.
The second variable is the “motion threshold” for terminating a Motion Event Upload Video. While the user does have a 100 point sensitivity setting to set for initiation of the Motion Event Upload, I have never seen official confirmation that the user set sensitivity threshold is also used for the termination of Motion Event Uploads. It is entirely possible that this may also be a firmware logic setpoint for which the user has no control. And again, if this is the cased and it is set too low in the firmware, it will significantly reduce the length of videos and cause a significantly higher number of uploads if the Motion Event Sensitivity setting is set high by the user.
The discussion of shorter length Event upload videos on Wyze cams has been going on for some time. I have had lengthy discussions with others who have also noticed a drastic drop in video length following firmware updates over the last year or so. But, the cause remains speculation unless someone from Wyze can confirm the specific logic being used to determine when a Cam stops recording.
I have my Events list filtered to only show me the Smart Detection AI Events. Currently, those Event lengths are accurately capturing the start to end of AI tagged events. But, this has not always been the case which prompted the discussion some time back.