Willis was originally scheduled to be sentenced for the murder of Jessica Heeringa on Tuesday, June 12; however, that has been pushed back to Monday, June 18.
The court said that Judge William Marietti does not normally do sentencings on Tuesdays.
Willis was found guilty in May of murdering Norton Shores store clerk Jessica Heeringa. He is already serving a mandatory life term for the June 2014 murder of Rebekah Bletsch, who was fatally shot while jogging.
►Related: After two murder convictions, what's next for Jeffrey Willis?
Willis is also accused of attempting to abduct a teenager in 2016. She escaped his van, sought help from a nearby resident and went to police, leading to his arrest. The girl, who was 16 at the time, testified at the two murder trials.