At which point does a divorce through text message occur? When the divorce is written or when the message is sent/received?
بِسْمِ اللهِ الرَّحْمنِ الرَّحِيْم
In the name of Allah, the Most Gracious, the Most Merciful
One needs to very careful in his issuance of divorce as divorce can take immediate effect. Divorce through text message does make divorce valid as soon as the text message is sent. If the text is sent multiple times, it will count as one single divorce each time, for example, two text messages stating divorce will stand as two divorces.
Only Allah knows best
Written by Maulana Irfan Ali
Checked and approved by Mufti Mohammed Tosir Miah
Darul Ifta Birmingham
 Fatawaa Darul Uloom Zakariyah, vol 4 page 53, Zam zam publishers