Pine phone : Drive read speeds ?

[bcnaz]

I am curious what the Pine Phone actually does in "drive read speeds".

 The eMMC drives and sd cards do each have their own speed ratings.

However in the end what matters is the speed that the phones mainboard can actually "use" them.

I may have 'missed it'   but I have not found this in the wiki, 

 I saw an older post that 'hinted' that the maximum sd card,  read speed by the board was 28mb/s.

 I am NOT asking for 'Favorite Brands' or '"Opinions"'....

Just facts :  How fast can the mainboard read each type of 'Drive'  ?

Thank you