NPO = Nothing by mouth (literally = "nothing per oral" ... lol )
Hey chosen... hope all goes well for you...
For the most part, following the criteria Dusty gave above, incisional hernia operations are usually done as she mentioned above. So it sounds like your surgeon is, like she said, being "pro-active" to omit any further complications.
I have had 3 full-open surgeries, and one laproscopic surgery, but have never had a hernia after (abcess yes...hernia no...lol).
That being siad, being a nurse and knowing how long, for example, women who have had C-sections stay in the hospital, I would guess about 2-4 days as well, as a hernia repair shouldn't be as intrusive as the resection surgery... However, I would still expect a couple of weeks rest at home afterwards.... again, thinking aobut my c-section moms...at least 3 weeks before you are up to par....
I wouldn't expect NPO afterwards, as again, it is a surface surgery... the intestine wouldn't be involved... but it would probably be clear fluids 1st day, full fluids 2nd day...and so on...as all anesthetics will slow the bowel down/put it to "sleep", so we wouldn't want to try a Big Mac right off the bat... lol
But that is just my best guess.... Good luck!!