My current understanding makes it entirely plausible to run out of cards in the probe droid deck.

31 (Probe Cards) - 5 (Starting Systems) - 1 (Rebel Base) = 25 In Deck

At a rate of 2 cards a turn, the probe droid deck will be empty at the refresh phase of turn 13 this makes it unlikely but possible. Adding in "Gather Intel" to the mix makes this a plausible occurrence though uncommon. If the probe deck is empty would you just no longer be able to draw from it (Rapid Mobilization)? Is there an event that involves recreating or putting cards back into the probe droid deck (Ignoring that one rebel card that puts 4 back into the deck)?

Once the probe deck is empty, the Imperial player knows exactly where the base is and can now focus on Massing forces to destroy it, if he has enough time that is.

Exactly what Rowdy said. When you've probed the entire galaxy, why would you still want to send probes?

I just wanted to confirm I understood the rules and wasn't missing something.

There are some cards that the Rebel can play that does put cards back into the probe deck. I am at work, so, I don't have the card in front of me. Rowdy? Do you know which card or cards?

There are some cards that the Rebel can play that does put cards back into the probe deck. I am at work, so, I don't have the card in front of me. Rowdy? Do you know which card or cards?

There is one Rebel mission I can remember off had that allows you to put 4 probe cards back in the deck. I don't remember the name. It might have even been an action card now that I think about it. Despite my familiarity with the rules and having played through 3 games before the game came out, there are some missions I only ran across once or twice. My demo that I ran at Adepticon was the EXACT SAME set up every time through.

A game really shouldn't go that long without a rebel completing objectives, which is pretty much what would have to happen for it to reach that point.

Plant False Lead. It can buy you 1 or maybe 2 extra rounds of play.

In my latest game, the imperial player didnt get/succeed in any of the non-basic droid cards but he was able to do Gather Intel on almost every turn for an additional card and 2 cards once.

By turn 7 there were only 4 cards left in the deck and he had it narrowed to 2 possible locations. He hit the base but not with enough force and I as the Rebels destroyed the Death Star for the won (would have also won in the Refresh).