Termination of the plan is not an exception to the early-distribution penalty.
Exceptions to the early-distribution penalty:
Presumably this is a qualified retirement plan. If termination of the plan results in a distribution to you, you can roll the distribution over to an IRA to continue to defer the income and avoid an early-distribution penalty.
if you have reached the age of 59 1/2 , then there is no early withdrawal penalty. however, you will pay income taxes unless you put the money into an IRA or other qualified plan. Maybe roll it into the new company's plan, if possible. if not, the best way to avoid income tax issues is to do a direct rollover to an IRA or other qualified plan. if you get the cash, you have 60 days to put it into a qualified plan.
Consult your plan administrator to see if your situation is considered a "separation from service."
If the plan is a 401K, it is an exception to the 10% penalty if the employee separates from service during or after the year the employee reaches age 55 (age 50 for public safety employees of a state, or political subdivision of a state, in a governmental defined benefit plan).
See Separation from Service in this IRS reference: