Mario X Rabbids may contain a hint as to what game Ubisoft is working on next.

[Soundwave]

axumblade said:
March 12, 1986 was when Ubisoft was created

EDIT: Yeah that's probably it ... UbiSoft Milan studio was founded in 1998, so I'm gonna guess Sept. 24, 1998 refers to that:

https://en.wikipedia.org/wiki/Ubisoft_Milan

They are the Rabbids dev team.