Anyone know what are the best tools to use to view changes in schedule frequency?

I noticed recently that the SFO/JFK schedules have been shifting on what in the past has been a pretty stable schedule. They used to run 2 redeyes (9PM-ish and 11pm-ish) a few days a week (I think Tues and Weds) which seems to have been cut down to just the 9PM-ish and the 8PM return (AA85) seems to have been cut to just the 6PM on most days I'm searching. Curious if they shifted some lift to JFK-LAX - I'm seeing 12 flights now and thought it used to be 10 or 11.