Since CDK seems less about customers, product and employees, and more about stock price, cost cutting and preparing for a sale, get familiar with the required filings by CDK on the www.sec.gov site, 10k, 10q, other "edgar" filings.
Or even a web search like "cdk global ceo contract" will turn up some interesting things.
Like when board members change or are added, when the CEO's contract is up for renewal, etc., etc.
If the things written here and elsewhere by current and former employees are accurate, then you likely can't count on "job security", and you probably can expect more surprises, drama, and seemingly erratic and arbitrary behavior by executive management.
Good luck, and get out on your own terms if you don't like the surprises and drama.