There are a few reasons why your SAT time might show different numbers on Khan Academy and on College Board.
1) The Opportunity Scholarship dashboard will update once a day, while the practice calendar and coach dashboard on Khan Academy will update more frequently. Make sure you've waited 24 hours to see your practice time show up in the scholarship dashboard!
2) The Opportunity Scholarship practice time only counts time actively spent working on questions, watching videos, and reading articles — whereas the practice time on Khan Academy reflects the overall time you spent with SAT web pages open on your computer. This means that for some people the Opportunity Scholarship dashboard numbers might be significantly lower than the numbers they see on Khan Academy.
If you are seeing time discrepancies that you don't think can be attributed to either of these situations, please let us know!