Thanks for reaching out. 
The recommended insecticide active ingredients for apple maggot management are carbaryl, malathion, or pyrethrins (Spinosad is not currently labeled for use against apple maggot in home orchards but can be used for codling moth control. This looks like a change in from recent years recommendations.)

This is where carefully reading the pesticide label is very important. Captain Jack is a brand name with several products being sold under that brand. Each of these products has a different active ingredient. 

• The Deadbug Brew contains spinosad
• The Orchard Spray contains sulfur and pyrethrins
• The Fruit Tree Spray contains neem oil

You can find this on the package or on the company's website (look for the pdf label on 'product literature'). The PDF version of the label is nice because you can print it or zoom in to see the small print. 

If you're looking for a Captain Jack brand product with spinosad for the codling moth then stick with the Deadbug Brew product. 

You may also want to install some apple maggot traps. These are red spheres that are coated with a sticky substance. The flies are attracted to the red color and then get stuck. This can help reduce the number of flies. You can purchase these online or DIY. 

Physically blocking the apple maggot from reaching the fruit can be effective. This involves bagging the fruit or regular applications of kaolin clay to the fruit. 

Let me know what additional questions you have!