Sender IDs will be overwritten as follows:
74800 Antel - Mostly dynamic Sender ID, but will sometimes be overwritten to ensure delivery.
75807 Movistar - Overwritten by a local numeric Sender ID, most of the time.
74810 Claro - Mostly dynamic, but will sometimes be overwritten to ensure delivery.
There are no additional content restrictions beyond those in our Acceptable Use Policy
Other features/restrictions of note:
Handset delivery receipts are supported in general from the local operators.