Cowen & Co. analysts in the retail and apparel sectors believe confusion over new seaborne freight rules could impact the back-to-school selling season.

The amended Safety of Life at Sea convention contains new weight verification rules for seaborne freight and go into effect July 1. In a Cowen & Co. report, analysts said there “appears to be confusion over implementation and enforcement.” They noted that the confusion could cause delays in seaborne freight throughout July as carriers adjust to the new rules. They also said that delays in the system “could affect shipping of products for b-t-s and benefit other logistics providers.”

The analysts — Oliver Chen, John Kernan, Helane Becker and Jason H. Seidl — singled out b-t-s because July is when retailers stock up for the shopping season. The report noted, “Any inventory flow disruptions may have an outsized impact on retail results as most companies are guiding to a stronger second half with back-to-school leading the way.”

The report also said that confusion could mean longer shipping times, which could result in some carriers considering air freight if shipping times increase during the implementation process. The analysts said during the West Coast port slowdown in early 2015, Atlas Air benefited from higher charter rates and volumes as more product shifted to airfreight. They also said the container lessors would benefit as well from longer shipping times as shippers would increase container demand because container turnaround time would slow.

According to Kernan, who focuses on branded apparel and footwear, noted that companies on the equity research firm’s coverage list have been preparing for the change and is “not anticipating a disclocation in merchandise flow.” But Kernan said that because the sector is already dealing with inventory overhang from a warm fall in 2015 and the West Coast port disruption, any additional dislocation in merchandise flow “could add widespread sales and margin pressure” at a time when operating performance is expected to improve. He also raised the possibility of potential inventory markdown or cancelled orders risk from delayed shipments.

Chen, who covers specialty apparel, said the potential disruption could require some retailers to rely on contingency plans, including “pulling forward receipts, and shifting from ocean freight to more expensive airfreight to ensure products arrive at stores on time.”

He cited specialty apparel retailers as most vulnerable. These companies include Abercrombie & Fitch, American Eagle Outfitters, Gap and Lululemon Athletica, as well as teen retailer Justice, a part of Ascena Group. Chen added that possible vendor lags could also negatively impact inventory levels at Macy’s, J.C. Penney and Kohl’s, as well as the Target and Walmart.

Chen said that off-pricers such as TJX Cos. and Ross Stores are likely to benefit from any inventory dislocation. TJX’s buying organization is across 11 countries and four continents, with the ability to source from 18,000-plus vendors in 100-plus countries. Further, a high open-to-buy level and lean inventory allows for flexibility to “capitalize on advantageous product opportunities,” Chen reasoned. In the case of Ross, Chen said the retailer’s “packaway program” could likely benefit from any port issues impacting the back-to-school season. He added that Ross’s packaway has a high turnover, with turns every three to four months, and the assortments have low fashion risk.

While handbag players Coach, Michael Kors and Kate Spade could face some headwinds from higher air-freight costs, Chen said the nature of higher-value product — in comparison to apparel — should yield smaller negative gross-margin impact.