Steamer and cyber have it right. ULA duties are 90% demos, 4% server side, 3% answering questions about rules, and 3% correcting misinterpretations about rules. The majority of my days spent on IBIS are doing one, two, or three of those things and it usually takes no more than 20 minutes to complete. Occasionally we each have asked for a period of time off and the other ULAs will take up the slack, no questions asked.
Simply put, a busy schedule does not prevent you from fulfilling the duties of the ULA position. You have to make the decision on whether or not you want to fit the small amount of time performing those duties in your busy schedule. Be honest with yourself and be straight forward with ZERO and the rest of the clan. If you do not want to perform IBIS' chores then just say so or do not submit an application. Do not waste people's time.