Why do my Email-to-SMS messages get truncated to approximately 70 characters?
It might be that a line break exists within the messages body. However, one of the limitations of Email-to-SMS facility is that new lines cannot be used within message bodies as they indicate the end of a particular value.
The solution to this problem is to remove the line breaks.
It might be that the email application used to send the Email-to-SMS message has 'word-wrapping' set and so the email application is placing a line break in the middle of the line. This would cause the same effect as mentioned above.
The solution to this problem is to de-activate word-wrapping in the email client/application used to send the email.
It might be that the email is encoded in Unicode (i.e. utf-8) and a Unicode character has been found in the message body. As such, depending on the setting for long messages, the splitting point might be set to a similar number of characters.
This problem can be solved by activating a suitable method of long messaging or not using Unicode characters.