Unable to restore a FAT split archive created using SBackup

I had backed up for a FAT Partition with 10 2 GB Blocks, totaling 21 GB approx. Now i am not able to restore the same, and the archive is not recognized by sbackup.

While backing up it created 11 2 GB blocks. These files are available as files.tar, files-2.tar etc., till files-11.tar. Only files.tar is available for extraction, by tar xf, even though it gives an EOF error. The full 21 GB file seemed to have been compressed / split, as all includes list show just a single archive file.

My harddrive crashed and i am not able to recover the data fully. Hence this data is critical. This was done around 11 months back. So not sure if the Sbackup version then and now is a problem. Since my system crashed, have no clue on the version with which the archive was created. The version file shows 1.5 in the archive folder.

What options exist:

1. Can i concatenate these files using tar --concatenate?.
2. Can i cat them together to one more file?.
3. Is there a chance that the files would have got corrupted, when i opened it one by one earlier?