H1B validity date vs being in status

[mah_nitin]

1. As per this line - "An alien on H-1B classification is permitted to travel outside the US and reenter during the validity period of the H-1B visa stamp on his/her passport.". Is validity period and being in status same things or different. Say you go on vacation outside country and in the mean time your employer fires you, you get out of status, but still you are within your valid period of stay. can one enter in US in this scenario.

2. Is there any cancellation fees associated with H1B cancellation. And is there any negative impact on employer if he/she cancels H1B