I did set the video to MOV but I still get a 1-2 sec gap. After a lot of looking about on various forums I did find a reason that made sense... ...the overlay will happen normally when you set the record size to a preset amount of minutes, ie 2, 5, 10 or 15 mins, but when you set file size to max, the mobius doesn't know exactly when to change file...so begins the new one when the 4gb limit is reached, hence the gap. If you had say a 5 min file size then I can see the software beginning the new file at 4 mins and 59 secs so you'd get the overlay. But, as the 4gb (...3.99gb usually) limit can vary on time depending on the info coming through the lens, there is no real accurate way of determining the end of the file until it reaches the limit, hence the gap.
...makes sense to me, is it correct?
...when you say the max file size of 4gb is by design, do you mean by the mobius design? Is there any way to override this to record a whole journey on one file? I understand your point on the safety angle but it would avoid the need for a lot of editing if the exfat could operate as it should.