I received only today the records you sent nearly a year ago.
It was not until November that I received the records which had been sent nearly a year earlier, in January.
Why in the second sentence past perfect seems obligatory. It is obvious that a year earlier is linked to until november and that is before november. Is it because until november draws the event "really" in the past where as received only today draws the event "not completly in the past". I don't know if my question is clear enough to be understood