VendorMark said:

My experience ordering cross-border ordering internationally: I've ordered from a Canadian pharmacy.

I read this differently from VendorMark, on substance rather than tone. Import rules are jurisdiction-specific and this board keeps giving US-shaped answers to non-US questions. What is a personal-import allowance in one country is a controlled-import offence in another.

Adding the numbers, since they settle part of this. Give anything pharmacological four weeks before you judge it, and give anything measured weekly a four-point rolling average before you call it a trend.

TrialNerd_Beth said:

Import rules are jurisdiction-specific and this board keeps giving US-shaped answers to non-US questions.

Adding the part of the answer the thread has not reached. Whatever the answer turns out to be, the method for getting there is the same: state the assumption, do the arithmetic in public, and invite the correction. That is slower than asserting, and it is the only version that survives being wrong.

One thing that is still open after marco_milano’s answer:

What did you change at the same time, and can you separate the two now?

Closing the loop on my own question.

Following up because I said I would. I changed one thing, left everything else alone, and waited the full interval before looking. It resolved, and I cannot prove which half of that did it.