Getting RTC driver working on i2c-3 (HyperPixel)

I’ve had some success with using the HyperPixel 4.0 with the PiJuice HAT (and the PiJuice Zero pHAT). However I haven’t been able to get the RTC (ds1339) working however, since the dtoverlays don’t expect it on i2c-3.

The symbolic link that is suggested doesn’t seem to work for this, and I’ve had no luck with dtoverlays (i2c-gpio-rtc, or even making my own with target=<&i2c3>; dtbo).

I’ve followed i2c-rtc-gpio the instructions at:

Sadly, no joy - i2cdetect -y 3 yields the address 0x68, but no UU (kernal driver not added).

I’ve also tried compiling my own dtbo overlay with target i2c_arm replaced with i2c3 (as opposed to i2c_vc per this link)
Still no luck.

Any help appreciated!