I'm not sure myself as I don't work with material versions. But it sounds like something related to that. The thing to understand is that the inspc lot start date can be influenced by several differnt type s of documents. So 04 lots can get their start date from the planed start date of the order, (I.e. When early lot creation is used). Its not necessarily always that the lot creation date = the lot start date.
hopefully maybe some folks more familiar with material versions might be able to shed more light on this.
Craig