This document is explaining the changes of Service tax posting. According to Kastam ruling, service tax is paid upon payment basis.
Step 1 -Previous version 2018.1.0.4 or 2018.0.0.4
Service Tax Code SVT-6% is posted to Service Tax Account
Step 2 - When posting in sales invoice, the posting to ‘SST Service Tax’.
Even though the payment is not yet received, but this will reflect in SST 02 – column 11 (c)
From version 2018.1.0.5 or 2018.0.0.5 onward
System will prompt reminder message during database upgrading for users who use service tax
So please update user about the changes.
1. Notice that there is additional column in SVT-6% tax code 
2. Go to GST/SSTS à GST/SST Account Setup à Apply [it will assign GL account for SVT-6%]
3. Back to SVT-6% in Tax code maintenance, notice that
Posting Account GL Account posted to SST-5000 SST Deferred Tax
Posting A/C Service (Payment) posted to SST-2000 SST Service Tax
4. If we create an invoice, system post to ‘SST Deferred Tax’ instead of ‘SST Service Tax’.
In this case, it WILL NOT posted to SST 02 form 
5. Where there is receive payment upon matching, system will
Debit SST Deferred Tax
Credit SST Service Tax
From this posting, it will post to SST 02 form based on the Receive Payment
If you have upgraded to this version, notice that the previous transactions will not reflect in SST 02 form. you need to resave.
Q & A
Questions 1:
My company is 2 months submission, I never submit before and going to submit on November.
After upgrading, previous transactions with SVT-6% is not reflect in SST 02 form, what should I do?
Answer:
Please resave transactions for Invoices, Debit Notes, Credit Notes and Receive Payments will do
Question 2:
I have submitted SST before.
After upgrading, previous transactions with SVT-6% is not reflect in SST 02 form, what should I do?
Answer:
Please refer KB - Service Tax Adjustment for Submitted Entries