SERVICE TAX PAYMENT

in service tax point of taxation arises earlier of the following
1) issue of invoice
2)date of receipt of amount

in your case already you have issued the invoice

so point of taxation has already risen u need to discharge service tax liability
in case if u have not paid service tax u need to remit service amt Along with interest and penalty.

generally, service tax quarterly payment for proprietary it means april to June quarter payment have to made in July 5th .
from July 1st onwards gst coming to picture.
shall we pay service tax or gst on July 5th

date of payment is not relevant . only point of taxation is only relevant . so u need to pay only service tax