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I work at a law firm and recently came across an intriguing case. When going through documents, I discovered that the suspects' text messages had been reproduced - times, numbers, and even content - and the information was extremely incriminating.

I am not sure when these documents were subpoenaed and obtained, but it made me curious...how long is the period where Verizon can keep all of this information?

I have been conducting research on the topic...many people say Verizon stores content for 10 days (and can be reproduced upon subpoena), but then after that only the general information can be reviewed. Others say it all can be found whenever with the proper research.

Pertaining to the specific case documents, messages spanning a total of 3 days (the days surrounding the incident) were reproduced. I can only guess that if it was possible to obtain texts from before that time, those past messages could further incriminate the suspects...but is it possible to retrieve texts from more than 10 days ago? I read that in other cases, text messages including content up to a couple years old have been reproduced. 

Realistically speaking, millions of text messages are sent each day - so how would the server be able to store that many text messages with their content?

Seems like a lot of questions, sorry. Just really intrigued by the extent of our current technology.