It is so weird, I performed the same for BW and ECC, they also have one entry for Prod SID in TADIR table. BW upgrade to 7.5 completed successfully and ECC upgrade is still running in one phase before MAIN_NEWBAS/XPRAS_AIMMRG. I remember performing SE06 and reconfiguring STMS. I am guessing this table entry may not be the problem and I completed BW upgrade successfully.
Thanks,
Kavitha Rajan