The U17 MLS Next soccer rankings will be available in Late October.
The reason for this is because the U16 age group is combined with the U17 age group at the MLS academy level. Due to this fact the MLS academies do not field U16 teams. And because they do not field any U16 teams there is no prior year history available to reliably rank the Overall U17 age group at the beginning of the season.
As the U17 MLS academies begin to play, more information will be available. And reliable rankings should be able to be created at that point.
Look for U17 MLS Next rankings to be available mid to late October.