Because a lot of "corrupted data" made it on to the leaderboards at launch, according to RedLynx, the multiplayer scoreboards in Trials Evolution will be reset when the patch goes live at 2:00 AM PDT Wednesday morning. Single-player leaderboards, player-created track leaderboards, and multiplayer ranks won't be affected by this change.
RedLynx recommends that players stay out of multiplayer for four to six hours after the update, in order to make sure that any scores earned are recorded correctly. What else can you do between the hours of two and eight AM? Sleeping is one option. Just throwing that out there.