As far as I know, one cannot have a pure vowel in the middle of a paadam in
Telugu. So, usually such words, beginning with vowels, which occur in the
middle of a paadam undergo sandhi with the previous word. A lot of telugu
sandhis have been defined, I feel, to accommodate this feature. For
example, to say
naaku atta agun
the combintation of the first two words may be written as
1) naakatta
2) naaku natta
3) naaku yatta
and the combination of the latter two words as
1) attagun
2) atta yagun
as required by the gaNa vibhajana rules.
When the praasa sthaanam falls at this letter, it is the corresponding
consonant which has to follow the praasa rule, not the vowel. After all, by
definition, praasa allows one to change the vowel.
my 2 np worth.
Nasy