DCL does not offer up free drinks all the time, so I say go and partake of some drinks and food, say hello to the Capt and Senior Officers, and Cruise Director (Rick is currently on the Magic) and have a good time.
The whole thing lasts about 45 minutes and can get very crowded. On our last cruise there were over 500 people return cruisers onboard...and I heard that have been even more than that at time. You can come and go as you please...there is no set agenda.
MJ