Transportation and delivery times are another issue. Movement of goods is the biggest problem. For example, major hauliers were found not be ready with the right paper from the beginning of the year. The firms that were ready were then inadvertently overwhelmed with deliveries, but things are already improving. Most companies have been trading in the UK for so long that unless their deliveries take weeks instead of days, it should not cause major issues. They would just need to get their partners in the sales channels to order the products slightly earlier than they would normally.
There is, of course, a benefit for companies that manufacture their products in the UK. Delivery will not be much of a problem for them, but then, their problem instead will instead be exporting.