【Updated: 】
The rankings for a particular period are calculated at approximately 10:00 PM PDT/9:00 PM PST at the end of that period.
Therefore, any changes to your score after that time will not be reflected in the results announced for that period.
Please keep in mind that even if you began a match before 10:00 PM PDT/9:00 PM PST, if it ends after 10:00 PM PDT/9:00 PM PST, then the score for that race won't be reflected.
Also, the score displayed for your Lifetime Best does not necessarily get reflected in the ranking results.
See the section labeled "The score displayed for my Lifetime Best is not reflected in rankings." for more details.