I do not think they have entered/shown the totality of the texts recovered.
I believe they are only showing texts they feel relevant to the case so as to not convolute their message.
If there's a period of time where texts are absent, I suggest it's because they were either
1/ not recovered, or
2/ recovered, and deemed irrelevant or inadmissible.
I get that, but there is a steady stream of texts throughout the month between DM and SS. It just shows that Smich was saying nothing relevant to the case in the weeks leading up to the event. In the TB crime there were incriminating texts galore in the days before. Nothing here.