On Fri, Oct 16, 2015 at 5:38 PM, Odhiambo Washington via skunkworks <skunkworks@lists.my.co.ke> wrote:

Are you telling me that Safaricom/Airtel keeps copies of all my SMS?

@Odhiambo, an age-inappropriate answer would be "duh!", hehehe. Anyhow, I remember vaguely hearing or reading that they keep them for 24 hours or something like that.

We could also deduce that they keep them for as long as they retry sending the SMS if the recipient is unavailable.