Very surprised a lot of you are giving these random rumors floating around any legitimacy. We should know better by now.
Let's be clear:
-T'Challa will have his trilogy.
-T'Challa won't be replaced beforehand. Why replace the star of the franchise before said trilogy? If I'm Marvel, I keep T'Challa around for as long as possible, for both economic and story reasons.
-T'Challa will have plenty of opportunities to shine. He's the multi-dimensional character of the film. Everyone else has one lane.
-In Coogler I trust, for obvious reasons. He'll do his thing.
Ignore the haters and the random rumors, you'll just get a headache from them.