One thing that is still open after sophie_paris’s answer:
What did you change at the same time, and can you separate the two now?
kate.chem said:Say what you would expect to see if you were wrong, before you look.
I am going to disagree with the direction of travel here. The thread has converged on the tidiest answer rather than the best-supported one, and those are not the same thing.
kate.chem said:Say what you would expect to see if you were wrong, before you look.
That is right for the common case. Whether it is right for the case being asked about depends on a detail that has not been given.
Ask again with the specifics and you will get a better answer than this one.
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Browse GL Biochemkate.chem said:Say what you would expect to see if you were wrong, before you look.
Saving this. It is the first explanation that did not require me to already understand it. Taking it to my next appointment.
OP back with an update, since a thread like this is useless without one.
Closing this out: the trough rather than the peak explains the pattern I was seeing on day six, which I had been blaming on the vial.