bpexpdate

Seems it is fixed, not an issue in 7.6.1.2

root@womble daemon $ bpexpdate -m TAPE01 -d 07/31/2016
Are you SURE you want to change TAPE01
to expire on Sun Jul 31 00:00:00 2016 y/n (n)? y

From scanning previous cases, this was apparently resolved in 7.6.0.4, but nobody ever identified the Etrack containing the fix.

After poking around a little more, I suspect you might have been experiencing the regression described in this TechNote, albeit with different symptoms:

BUG REPORT: The bpexpdate command may produce a core file
 http://symantec.com/docs/TECH225116

On Solaris, this defect caused core dumps, but you say you're on Linux, so maybe things were being handled a little more gracefully.

If you're still on 7.6.0.3, you can see that it still works for you, but if it didn't, you could add -force to the command line and work around seeing that incorrect prompt (per the TechNote).