Hi Jay,
Please note as per following points
Step 01-
while making advance payment to the vendor as per below method
Expense value-100.00
Service tax -12.36
Total Bill value= 112.36
after Deducting TDS on base value(100*10%)= 10.00
Now you are making payment to the vendor is Rs 90+12.36=102.36
Step 02-
After receiving actual Bill in the month of July Service tax rate has been changed from 12.36 to 14%
Now wants to book the invoice is as per given below
Expense value-100.00
Service tax ----14.00
Total Bill value= 114.00
Deducting TDS (on base value(100*10%))= 10.00
Now you are making payment to the vendor is Rs 90+14=104.00
Earlier you already make a payment to the vendor is Rs 102.36
This differential amount is Re 1.64
Final solution is very simple at the time of invoice booking you can adjust the differential amount in withholding tax tab.
One more things ensure this service tax amount borned by vendor or Receiver.
if Receiver making service tax payment means his responsility to differential amount to be adjust in at the time of invoice booking with reference of advance payment entry
Hope it is cleared now.please revert if any further clarrification