There doesn’t seem to be an official deadline for this to be implemented yet, or exact details of what it will entail, but we’ll definitely update the article when it becomes mandatory.

Unless you’ve given the numbers out to people who happen to call while the other SIM is installed, nope, no downside at all.

Hi – do you have a link to the Amazon product listing for the E5885 with the reviews you mention? The only one I can see on the US Amazon store has a passing mention from someone using a Google Fi SIM in Mexico saying it didn’t work, but a few others saying local SIMs work fine.

Hmm. I don’t know for sure what’s causing that — usually I’d say that the package wasn’t activated properly and you were using data at the casual (expensive) rate, but that seems relatively unlikely if you bought it from the official airport store. If simple things like rebooting the phone don’t get it working again, unfortunately you’ll probably need a trip to a Telcel store to sort it out.

I don’t think I could use up my data in 8 hours and most of the social media is unlimited usage in my package.

You might save a little bit by already having the AT&T SIM (if it’s still active), but I doubt there’d be much in it. Personally I’d probably just find the nearest Telcel outlet to my accommodation.

If you did want to try your luck with the AT&T SIM, though, Google Maps suggests there are both AT&T and Telcel outlets in the Lago Real shopping mall outside Nuevo Vallarta — so if you did want to try to reuse the one you had and found you couldn’t, you’ve then got the choice of buying a new one from AT&T, or getting a Telcel one instead. Of course, that’s all assuming Google Maps is correct!