There will be no big megapixel announcement in april.
First Canon has to replace some lenses like the EF 16-35 II L, the EF 17-40 L ...
Both lenses don´t work pretty with the big megapixel prototypes.
Seems like you may have some inside info here.. I don't know how or what exactly you are testing but if its the big MP prototypes I really wish it will concentrate on noise in shadows at low ISO first , then DR not just on MP.
I get the feeling the 47mp monster that has been mentioned recently might be overkill and 40mp max may be a perfect balance when considering lens's performance too.
Also other considerations for a potential MFDB competitor should be be flash sync that would help a lot of people struggling with canon 1/200th sec for location flash scenarios ( and please don't pipe up with speed lights HSS everyone, as for proper professional work speed lights don't cut it, especially when it comes to power and ability to use bigger modifiers). So is it possible to feedback to Canon that 1/500s + flash sync for external units should be a priority to help this camera be used in a proper high end way.
This together with L primes will be a game changing camera at half the cost of a hassy or phase one but with much much more features and usability.