ESB is non contributory and is wholly for company account. If you are on some sort of special deal, you may not be entitled to it. I believe that the contract has to specifically mention that there is no ESB.
Summary dismissal would result (in most cases) in denial of the ESB.
Don't expect termination pay if you are fired as some companies will resist payment.
Don't count on a few months on your old salary if it is summary dismissal.
After 15 years, I was released (not summary dismissal) and was asked to be "out" in a week. I was not amused and it took 5 weeks.