all the B12 releases seem to have had trouble (for me anyway) discerning the difference between Home and Away

There was news of some of the releases getting confused about whether they were on AC or DC, but this has been fixed as I recall. And when it happened, this wasn't EQ-specific, it affected all the other home/car stuff like volume.

with both preset sets having the same names - edit one in the car, the name changes in the home also

That's by design. There are only 16 presets and only 16 names. Each one has two "personalities", home and car, but they share the same name. In other words, you shouldn't be naming your presets "home" and "car", you should be naming them "more bass" or "treble cut" or whatever.

This week under 12C Mk1 I have seen all my car presets appear at home when under AC power.

If you mean the names, then that's by design. If you mean the settings, then that should be reported as a bug (unless it's simply because you programmed the settings when there was still a bug with the home/car detection).

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Tony Fabris