This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.
Picking up post #88: that is the part I would want checked first.
The version of cold packs that circulates here is a simplification of a simplification. It is not wrong, but it has lost the conditions under which it holds, and those conditions are where the interesting cases live.
Document outcomes rather than forecasting them. A forecast in this category reads as reassurance and is not one.
Declared contents and declared value are the two fields most likely to cause a query, and accuracy in both is the only strategy that survives.
If that is already documented somewhere, ignore me and link it.
Same experience here, different supplier, so it is at least not unique to one of them.
What I would want before treating cold packs as settled: the method, the sample, and whether anyone tried to find the opposite result. Two of the three are usually missing.
Answering the cold packs question as asked, then the question I think is meant. As asked: yes, with the qualification below. As meant: it depends on how the first measurement was taken.
At what point is a parcel genuinely a problem: if it was despatched weeks ago and there has been no update for days at customs, it might be held or lost. Days of delay at customs without update is ordinary; weeks without movement warrants inquiry.
If this contradicts something upthread, the upthread version may well be the better one.
Small correction to my own earlier position on cold packs. I had the units the wrong way round, which changes the conclusion by an order of magnitude and therefore changes it entirely.
That matches what I have seen, for whatever a single anecdote is worth.
Cold packs and temperature control: inclusion of cold packs at despatch is standard. Whether they maintain temperature through transit depends on journey duration and ambient temperature. Long journeys through warm climates put product at risk.
I would want to see it done twice before believing it once.
Post #102 is right about the mechanism and I think understates the practical bit.
Import restrictions by jurisdiction: what is legal to import for personal use varies enormously by country. Some jurisdictions are quite permissive; others are not. Checking your own country's rules before ordering is prudent.
Tracking stops updating: tracking last updated days ago usually means the package is in transit and will not update until it reaches the next scanning point. No update for weeks means it might be stuck.
The short version is the first sentence; the rest is why.
Building on post #106 rather than restating it.
At what point is a parcel genuinely a problem: if it was despatched weeks ago and there has been no update for days at customs, it might be held or lost. Days of delay at customs without update is ordinary; weeks without movement warrants inquiry.
Saving this. It is the version I will quote when the question comes round again.
Worth separating two things that post #112 runs together.
Cold packs came up in a thread eighteen months ago and was answered well. I cannot find it, which is itself the problem, so here is the reconstruction.
Counterpoint on cold packs, offered without confidence: the same observation is consistent with a much duller explanation, and nobody has ruled the dull one out.
Document outcomes rather than forecasting them. A forecast in this category reads as reassurance and is not one.
Peak periods and public holidays affect this more than any other factor and are entirely predictable in advance.
I have kept the units in throughout, for the obvious reason.
I had written a reply contradicting post #115 and deleted it. Here is what survived.
Declared contents and declared value are the two fields most likely to cause a query, and accuracy in both is the only strategy that survives.
Confirming post #119 from a second method, which matters more than confirming it from a second person.
Delivery to an address where somebody is present is worth more for cold-chain material than any packing decision available to the supplier.