The phrase "upon a change" is correct and can be used in written English.
It is commonly used to indicate that something will happen or be affected as a result of a change that has occurred. Example: Upon a change in government, there was a significant shift in policies and priorities.
But Presumed Innocent depended upon a change in public attitude: lawyers were no longer idealised figures.
The band regrouped, and decided upon a change of direction, with new songs and new name.
To insist upon a change from mental health to brain health is not merely a linguistic issue but also a fundamental shift for professionals, patients, families and caregivers.
This was contingent upon a change in North Korean behavior and an eventual North Korean pledge to the world that it would not embark on the road to nuclear weapons.
A few months prior, Steve and I had decided upon a change in our lives: certainty in the form of a bi-weekly paycheck was traded for joy in the form writing time.
Today, about 82 percent of the chiefs of Standard & Poor's 500 companies are entitled to some type of cash payment if they are replaced upon a change in control, according to GMI Ratings, a corporate governance firm.
Maybe people needed something they could rely upon for a change; something more dependable than their banks and politicians.
Upon detecting a change, they raised their tool and pointed it at the changed item.
Upon detecting a change in network location through the comparison of domain name prefix, MCS sends a PREG message to announce its movement event.
The sort of strict law pointed to depends upon whether a change in vocabulary is required in articulating the conditions gestured at in the ceteris paribus clause.
Therefore, upon such a change in parameter values, acinar cells lose their exocrine markers and dedifferentiate spontaneously.
