The OTP that first struck my mind wasn't the one that you ment, but then again: this is FT and the BA/BAEC subforum, so...

As for EU261 and mechanical faults: I think it's good that it also covers it, because it hopefully pushes carriers to keep planes operational and take perhaps better care of their technical condition with more foresight, so that perhaps fewer IRROPS would occur due to delayed maintenance and just doing the bare minimum. The Canadian adaptation will mean that there's no incentive to push for better maintenance, if you can't be held liable and pay a delay compensation as you postponed maintenance.