I've notice the values of older models drop once Panerai introduces similar looking watches.
Years ago. If you wanted a PVD model. You had to buy an older one which drove the prices up. Panerai seeing this. Decides to produce PVD/DLC models again to get in on the action.
Of course people no longer have to buy the older models and prices fell
Same for a number of other older Panerai models.
Lowest price on a older Mare was $13,000. Others asking around $15,000
Once the new ones are more widely available. No real reason to buy the older models unless it's the tritium dial you feel add's the extra cost to the watch.