My hypothesis is that MCU has been developing a built-in fanbase for long and ever since Infinity War there'll be hardcore group that'll turn early ala Star Wars. I think we'll start seeing Star Wars like internal multi for MCU too.
Maybe the women's day and feminist angle might help but I don't think CM will have the kind of walk-ins that pre-IW MCU films used to have
Since CM's selling ahead of BP (I know percentages matter), what are the odds that it opens to $183M, thereby taking the all time #8 opening record from Incredibles 2?