Based on the events currently ongoing, the next units most likely to be released from the JP version, and the dates for our chances for UoC tickets this month, it appears the most likely schedule for the rest of July is:

• 7/12 - Raid: FFVII (Zack and Yuffie)
• 7/19 - Mog King: FFXIII (CG Lightning and Future Hope)
• 7/26 - Raid: Collab (most likely Just Cause and Rico 7*)
• 7/31 - Story Event: CG Elena (Tues. maint Wed. start)

Zack and Yuffie seem most likely for the 12th, unless they plan on delaying them even more to the 26th.
The 19th is the earliest we can start another MK, as both King Mog and the Mog Minister will be tied up with the 3rd Anni KM and FFVII KM ships until the 18th.
The 26th is the more likely slot for a collab, though technically it could be on the 12th. Just Cause seems most likely, but we're also quickly passing our window to get the Octopath collab.
CG Elena is confirmed for July, and she's the only reason I can see them doing Tuesday maintenance to start an event on a Wednesday. A story event is also the only event type you can do that with, without potentially overlapping with another event's schedule and causing problems.

Edit: As pointed out by /u/Dawn_of_Ashes, the VII Raid gives Moogles for Barrett and Cait Sith, so if you haven't already fused whatever dupes you got from the Red/Aerith banner like I have, hold off on doing so.