Letter 'Z' pronounced as 'Izzard' : how widespread and where?

I read at Which is the correct way to refer to the letter "Z" — "Zee" or "Zed"?
that the letter Z is pronounced :

‘Izzard’ (/ˈɪzərd/) in Scottish English.

as opposed to zed or zee.

Question: Is this really the case in the modern day or is it archaic? Do people really use this in Scotland or elsewhere?

I ask as I’ve never heard anyone use Izzard in my life (and I live not a million miles from Scotland). Regarding the history, the American Heritage® Dictionary says:

Word History: The curious and charming word izzard, meaning “the letter z,” is practically limited to certain fixed expressions in American vernacular English, such as from A to izzard, “from beginning to end,” and not to know A from izzard, “not to know even the most basic things.”

The English lexicographer Samuel Johnson mentions the word izzard as part of his attempt to explain the sound of the letter z in the grammar of English he placed at the beginning of his Dictionary of the English Language, published in 1755: Z begins no word originally English; it has the sound, as its name izzard … expresses, of an s uttered with a closer compression of the palate.

In Johnson’s time, a variant name for the letter z, uzzard, was also in use. Izzard and uzzard are related to zed, the usual name of the letter z in British English. In Scottish English, z was also once known as ezed, and this form gives us a clue to a possible origin of izzard.

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