i was having a similar problem in that I was showing up as a general skymiles member for a few days, but it did come back. I was communicating with kevin pinto (that awesome skymiles manager from delta) and asked him about it. he advised me that they were running end-of-year reports on skymiles, so we may see "squirly data" this week.

i wouldn't worry about it unless it persists beyond this week...