Something similar happened to me earlier this year. I had a buyer purchase six coins and forgot to enter the tracking number for the other five which did not have a label printed. This dropped me below the 95% level. I talked to an
ebay rep who told me about the "grace period" and said that it shouldn't be a problem, then later I was notified I had lost my TRS status. It took me two months to get back up above 95% and just this last week my Top Rated Seller status was reinstated.
It was a learning lesson for me, too. I now always check on multiple orders so that all the tracking information gets entered.