Treat the invitation as positive only in the basic sense that the firm wants to interview you. Do not infer a special scoring advantage or lower interview bar from the timing.
Once you have the interview, your priority should shift to performance. The McKinsey first-round interview guide is more useful now than trying to decode why the slot was offered.
If the date creates a prep problem, ask whether a regular slot remains available. A good invitation can still turn into a bad outcome if you take the interview before you are ready.