Well, thanks for the enthusiasm. However:
1) The sellers of the units have all asserted that the unit starts out in Japanese.
2) I have indeed followed up with them and asked whether it is possible to change language to English. They have all said "no" thus far.
3) In fact, I was originally alerted to the issue when the seller of my first unit let me know that the device and manuals were in Japanese *only*.
4) The English manual I downloaded for the unit does *not* include language among the menu options *at all*, a most curious omission.
The above notwithstanding, I would still love to assume it is possible to change the unit language.
However even you yourself have admitted that there is no evidence of language change for the RH1 sourced from Japan yet.
Does your Canadian RH1 allow you to set its language to Japanese, for instance?
That would be a start.
Please let me know - thanks!