St-3 filed through excel utility

I filed an ST-3 using excel utility provided. On uploading xml file, I clicked on save button, instead of submit. Few hrs later the status shown is FILED. I have following queries:

1. Do I require to send a signed copy of ST-3 to department. If yes then do let me know which file should I use to take printouts from. What will constitute the acknowledgement for filing the return?
2. The assessee has a different premises registered with different STC in some other city. Does the assessee require to creat a separate account for this premises for filing online ST-3 or the same account can be used for the same. In case the same account can be used, how will the second require will be filed for the same period?

Thanks.