The meeting started off-schedule by half an hour due to technical issues.

off-schedule 是由前缀 off-（表示"偏离"）和名词 schedule（时间表、计划）组成的复合形容词，字面意思是"偏离原定时间表的"，即"比预定时间晚的"或"不在计划时间内的"。