Depreiciation calucaltion with new values

Hi Vaishali/Monika,

we are planning to add values in Segments , 

Now product dont have any values so we are planning to add values in PRODUCT Segment.

ex: - 1. Default (existing)

        2. Chennai

       3. Mumbai.

with adding new values we dont have any impact on OLD data (depreciation)

my question:

1. i want to update code combination for existing assts ( becasue i want to select prodcut values)

2. For new asests  -- no prob (while creating i will select the code comnibation)

3. For updating the code combination we have API.

4. if we update code combination any impact is there on (old/new) accounting?

5. Any problem for retairment , reclassification or any where ?