Melissa'a sweater covers either both or one shoulder intermittently when she is asking Jeremy to meet her at the pier at 8.
The number of buttons unbuttoned on Jeremy's shirt changes when he sings I Still Believe on the beach.
An Airliner's departure is filmed from a taxiway, which has blue edge lights, green centerline lights, & a solid yellow centerline. A runway has white dashed centerline markings & doesn't have blue edge lights.
Radio Station Error at the opening shot of the radio station at 1:07:10, you can hear the on-air personality welcoming in Camp, but there are no levels being shown on the Program Vu Meter.
When Jeremy is reading the journal notes that Melissa left for him in his guitar the written note says "lots of time" but we hear her voice in his head while he is reading it say "a lot of time".
When Jeremy meets Melissa on the beach and she asks why he is there, he answers with "I walk this route every morning." The sun is rising over the ocean, and given that the movie takes place in California, the sun would be rising in the West, which is incorrect.