Christ took our sin punishment, not our sin nature. Now while our Great High Priest is making atonement for us, we should seek to become perfect in Christ. SDA's teach that though saved by grace, we are kept saved by keeping the Law. This is partial atonement. Therefore, to stay saved according to SDA's, we must continue to keep the Sabbath, the 10 Commandments and pay the tithe.
Investigative judgement means no assurance of salvation.
SDA's teach that Christ transferred the record of believers sins to the heavenly sanctuary, which will be finally cleansed at the conclusion of the Investigative Judgement, their day of atonement. It would stand on record in the sanctuary until the final atonement. Hence SDA's sins are not cancelled or forgiven yet. What a worry. No wonder they have no assurance of salvation until the imaginary Investigative Judgement is finished.