Encoding scheme, Number of Digits parameters, GTI in SUA message

Hello!

I had two questions trying to understand a problem with GT in SUA.

1) Why is the encoding scheme parameter normally present in the SS7 messages absent in the SUA message as a parameter. In the absence of the encoding scheme in the SUA Called party GT, how does the SUA NIF analyze the digits.

2) The number of digits in the SUA message (called party) is already known depending on the digits included, i.e if I have a GT of 0123456789, then I have 10 digits. In such a situation where the number of digits present is implicitly known, why do we have an other parameter " Number of Digits" to tell the same? What is the significance of this parameter?
In most cases, GT is a phone number, why would we want to use only part of it for processing the message? (there would have been a wildcard GT provisioned for the destination(s) on the SG/STP to handle the case of using a subset of the digits.

3) Also, in section 3.10.2.3, the text
<snip>
0001 Nature of Address is taken over
<snip>
What does "taken over" mean? (Sorry, I don't mean the English meaning of it but taken over in this sentence : When there is an explicit Nature of Address parameter in SUA messages , I don't understand what is taken over here?)

4) ANSI specs and ITU specs for message format for different GTI values are different
Example :
ANSI GTI 1 : Global title includes translation type, numbering plan and encoding scheme
ITU GTI 1 : global title includes nature of address indicator only
SUA RFC only specifies ITU spec Q.713 reference.
Is it just for an example, and that similar formats should be used from ANSI or other specs wherever possible?
Or is it to say that the format for the particular GTI is now redefined with the SUA spec and this should be used?

Regards,
Satya