Answer
No — directly altering a core IFS database table's column definition, even something that looks as simple as extending a char field's length, outside of an official IFS release/delivery is strongly discouraged. The real risk is that many other parts of the framework, validation logic, other views, APIs, reports, or even a future IFS update itself, may implicitly assume that column's original defined size, and a manually-widened column might not cause any visible problem for a long time, only to eventually surface as a serious, hard-to-diagnose issue once something elsewhere in the system finally depends on the original size assumption in a way that breaks. All structural database changes like this should go through an official IFS release/delivery process rather than being applied directly at the database level, however inconvenient that may be for a specific one-off customer request.