16 years in the UK, never seen it used anywhere.

"used occasionally in some special contexts such as broadcast TV" is not what I'd call fairly common!

Never encountered it in half a century here, just military time "0 3 hundred" as used on the shipping forecast, or simply 3am.

I know it's common for commercial properties (bars, restaurants) to use it in Japan to show when they stay open past midnight. I remember being intrigued the first time I saw opening times described like that, and never seen it elsewhere in the world (including the UK).

Atleast i have never written or seen anything greater than 24:00 or 00:00 in time related information here in Asia; India & Middle East, working with British & Asian teammates. I am an Indian, by birth, age in 30-35 year range.

Theo only time I have come across is when I had to count the hours between two times in an excel sheet & found that by default MS Excel formats 25:00 hours to 01:00 & I need to use [hh]:mm to bring it to 25:00

Not according to the article you quoted: "... not commonly used ... they have been used occasionally in some special contexts in the UK ..."

I've lived in Scotland and England most of my life, and can't recall ever having seen it and am now curious about what these special contexts are.