Sorry my chart is not linked, but I had a fall back temp at 3dpo (just below coverline) of 0.4 degree and then my temp climbed to the highest point yet and on 7dpo it dropped 0.7 degree but was just above coverline by 0.1. Then on the day I got my BFP (12dpo) my temp dipped so low (1.3 degrees) and well below coverline I was sure I was OUT and almost didn't test. I'm glad I did! I'm not sure why the temp dropped so low (further implanting??), but it went back up and stayed up until I stopped temping (18dpo).
My previous cycle (BFN) i had a temp dip of 0.5 on 8dpo to just below my coverline...though i missed a few days temping that cycle as I was in Paris and not as focused on temping.
Not sure if what I wrote is helpful in the least, but there it is. :)