Photo Time Stamp Issue

I recently conducted a UAV mission and noticed that there was a time stamp issue on my photos.

The mission was programmed to automatically take several hundred photos and land. Halfway through the mission it was paused and the battery was changed to resume the flight and continue taking photos. When looking at the photos from the mission on my computer, I noticed that the time stamp of the photos taken after the battery change were earlier than when the photo was actually taken by several minutes. We have conducted this same mission several times before with the battery change and have not had any issues. We did not change any settings or alter the mission in any way during the battery change either. I have attached a screenshot of the photos in file explorer from the mission with the incorrect time stamp (image name increases by 1 for each photo taken. i.e. DJI_001, DJI_002 etc..., Images in the 300's were taken about 15 minutes after the first photo was taken.) 

What could be the cause of this issue and is there any way to prevent it from happening in the future? Thank you.