I think Niantic is going to keep cycling through the Legandary Birds over the next two Months. Moltres, is the current reward for completing a weeks worth of field research. I predict Zap and Arti will be available for field research next but not available in raids until later this summer. Legendary Dogs were rotated around the Globe for 3 Months during a high travel time (Aug 31st- NOV 1st). For that reason I foresee them coming back but not next. When Latios and Latias switch regions on May 8th the question is are we going to see Niantic implement another Raid Boss to keep its core base of trainers raiding? I think they will, but I have a suspicion that bigger things are in the works than adding another raid boss in Q2. With maps, bots, scanners, etc down Niantic should capitalize on creating their own in game map of nearby raids. Most likely we’ll get the regis as a concellation prize as not too many people I’ve spoken too about their release are all too excited for them.