nRF52840 with SoftDevice s140, rev 7.01. For this errata, the work around is to use READY instead. Is the SoftDevice doing this? I can't find any info. I did find a related question here: https://devzone.nordicsemi.com/f/nordic-q-a/35555/is-someone-out-there-actually-using-the-nvmc--readynext-register-on-nrf52840
Thanks,
Dean