Smart Recording Logic

I'm trying to unpack data from activities recorded with Smart Device on and I'm looking for something definitive that describes the logic. For example, I understand that the time field is used to determine when a gap has been encountered (meaning the data didn't change for some time). What I don't know is do I pull forward the current value or the previous value when I encounter a gap in time.

Thanks in advance for any guidance or pointers to a document describing how the data is handled in smart recording mode.

Apologies in advance if this isn't the proper forum. Please direct my as needed if a better forum exists for this topic...

Cheers,

Mike