Months. Of fuel and losses. And the production/gathering itself, which had to happen on some scale in one place or another.

I'd have thought that sending some ships with machinery and just living out of them for the duration it took to fill up the transports would have been more efficient than literally sailing to the other side of the world.

I.e. send a bunch of ships with basic "infrastructure" (machinery, tools, quarters) when spring started, then send a lot of large transports which could carry fuel and supplies down, and ice back up, until the season was over. No permanent bases required.

I think so. I had British friends growing up (in California in the 90s/early 00s) and drinking room temperature beer was something they were familiar with (though not a fan of). But by the time I visited Britain myself (2010) their pubs were as refrigerated as I would expect in America. I'm guessing that it was already well out of the norm by the 90s at the latest.

If it was 240 tons over a period of decades, it could probably have been used for minor industrial and artisanal purposes that weren't strictly high class luxury. That's a lot of ice and it's not like Perth had a huge population overall.