Oil level went down after starting engine because of filling the filter.
And didn't take as much because using the vacuum tube does not get out as much oil as draining it.
I drive mine on ramps and drop the belly pan and drain mine and I usually put about 8 qts or maybe alittle more back in.

Taking out more oil than you put back in to get to proper level could be due to being over filled before, you said it was about 1" above.