If the delinquent assessment remains unpaid on the date fixed for the sale under RCW
86.09.496 and
86.09.499, the parcel shall be sold in the same manner as provided under *RCW
87.03.310 through
87.03.330. If the district reconveys the land under *RCW
87.03.325 due to accident, inadvertence, or misfortune, however, interest shall accrue not at the rate provided in RCW
87.03.270, but at the rate provided in RCW
86.09.505.