I'm Miles from the Social Care team at Shopify. Thanks for reaching out!
We have two types of paused plans. We've got pause and build, where you can still access your store and storefront but with checkouts disabled and we have full pause, where you cannot access your store until you're on a paid plan. If you're on the Pause and Build, you'll still be charged for apps, as they will still be functioning while you access the site. If you're on the full pause plan, then app charges will be frozen.
One thing to keep in mind, app charges are charged a full month, no matter how long they are installed, so if you paused your plan mid billing cycle, it's likely that you will be charged a full month for any apps before the charges are frozen for the remainder of the full pause.
If you believe you have been charged incorrectly for any apps, you'll need to reach out directly to the app developer for assistance. Let them know why you'd like a refund, and if they approve it, they'll pass the approval onto Shopify so we can then process the refund for you. You can find the details for Aftership support here.
While you're on the paused plan, it might be a great time to check out Shopify Compass. This is our brand new free online course to help you get started with Shopify. We have courses on business, store design, marketing and heaps more! Coupled with some free live webinars, this is your one-stop shop to really get ahead of the curve in your business.
Have a great day!