AIM-listed potash development group Sirius Minerals surprised the market on Thursday after deciding to withdraw and resubmit its application for developing facilities at the York Potash Project, the world's largest polyhalite deposit in the UK.Polyhalite, which contains potassium, sulphur, magnesium and calcium, is a natural and organic mineral used in the fertilisation of crops.Sirius is seeking a development consent order for the proposed Habour Facilities at Teesside but has withdrawn its current application "with a view to refining certain options"."The purpose of the resubmission is to facilitate a more efficient examination process," Sirius said.The company plans to revise the application and submit it again the "near future", but has assured investors that it will not affect the overall planned timescales for the project.Nevertheless, the stock fell 7.4% to 8.34p by 16:20."Despite the positive rationale outlined by the company and its reassurance on timelines, we do not believe the market will react particularly favourably and expect that the shares will be down today," said analysts at Shore Capital.