Some months back, my daughter Maria Yagoda alerted me to a vogue word she’d encountered in the food-and-drink world, which she thought was a Britishism: “bubbles,” as a synecdoche (part signifying the whole) for Champagne or more broadly sparkling wine. I took a stab at researching it but was defeated by the sheer abundance of uses of the word in all sorts of context, including non-synecdochical wine discussions. (E.g., “I love Champagne because of the bubbles.”)
But then I was walking in Manhattan and came upon this two-sided sign:


So, not only “bubbles” but also “brekkie” and “mate“: a veritable NOOBs-orama! My enthusiasm was dampened a little bit when I found out that the advertised enterprise, Bluestone Lane, was founded by a former Australian Rules Football player named Nick Stone and describes itself as “bringing Aussie café culture (and better coffee) to the USA.” Clearly, the signage is leaning in to the Aussie identity.
In any case, the Bluestone sign inspired me to research the issue. I found, not surprisingly, that the more common term in both Britain and the U.S. has always been “bubbly.” (That isn’t synecdoche but rather a nominalized adjective. I”ll also note that in hip-hop, the preferred term has been “bub.”) According to Green’s Dictionary of Slang, “bubbles”=sparkling wine actually first occurs in a 1945 American dictionary of criminal slang. But that appears to be a bit of an anomaly, as the next example I have, from the OED, is from a 1989 Brisbane, Australia, newspaper article: “The 1986 pinot chardonnay bubbles..will cost about $22 in the bottleshop,..close to the lower-priced French champagnes.” That might be an outlier, too, as the next cite (from Green’s) doesn’t come till 2010, in a South Africa newspaper: “Sip a glass of seriously posh bubbles.” The term had reached Britain by 2018, when a novel had this line of dialogue: “’I’m going to have some more bubbles; do you want a glass?’”
By that time, “bubbles” had arrived in America. The OED quotes a line from a 2017 romance novel by K.A. Linde: “We need ice cream and bubbles to celebrate.” And an undated article by an American wine writer has the line, “You should also know that the French government has strict rules for Champagne makers… and if they don’t comply, they can’t call their bubbles ‘Champagne’ either.”
Clearly, I don’t have an abundance of data. But the evidence would suggest that “bubbles” had emerged in South Africa and possibly Australia by 2010 and subsequently spread to the U.K and then, fairly quickly, to the U.S.
Update: After getting some blowback in the comments along the lines of “I’ve been British all my life and I’ve never heard of such a thing,” I decided to investigate further by searching for “have some bubbles” in a few recent corpora. News on the Web (NOW), which tracks usage from 2010 to the present and has some 17.5 billion words of data, had thirteen hits. (There are fifteen in the graphic below, but numbers 4 and 5 are the same, and 13 refers to the bubbles in pancakes.)

The nationalities are six from Australia, four from New Zealand, one from the U.K, one from Hong Kong, and one from the United States — but that really doesn’t count since it’s in a quote from someone from Northern Ireland, and the reporter defines both “bubbles” and “craic” (a laugh).
And that’s where we’ll have to leave it for now.

Bubbles not one I have ever heard or read before.
Yes, same here.
I’m English and know the terms fizz and bubbly but have never heard bubbles in this context. My wife is Australian and she said the same as me.
I’ve never heard of bubbles in that context. With no other reference point, the word would just make me think of West Ham.
Thanks, everyone. See update, with evidence that the term is still most common in Australia and New Zealand.
We’ve been using “bubbles” in Sydney since at least the the 1990s. We also use “bubbly”.