ICAO/IATA Dangerous Goods Regulations strictly dictates the rule on the size and color of the labels. The minimum dimensions of the label is 120mm X 110mm which can be made smaller (105mm X 74mm) should the size of the package are of such dimensions such that they can only bear smaller labels. The border of the label must have red diagonal hatchings. Text and symbols black on a contrasting background. The explanation under DGR Figure 7.4.H uses the word “must” which means the condition is mandatory and binding.
Lithium batteries in today’s airfreight industry is a “hot item”. Airlines are rejecting shipments that do not conform to the regulations. I assume you have printed the packages with the blue label which may be costly to remake. Even though the chances of acceptance is very low, you may wish to explain the situation to the airline and see if they would deviate from the rules. “A package not in conformity to the regulation may contain hazardous articles” is the general psychological concept of the airlines in maintaining safety.