No Auto Default Address Swap

I tried this app for free. I like it very much this App.
I want to pay a one-time fee.
Do I have to cancel my subscription once?

Updated- This app is trying to solve for an obvious product bug (online comments about it date back to 2015 so shopify is obviously not interesting in fixing it) where the most recent shipping address changes the account "default" address, rendering that meaningless and screwing up our CRM and accounting data repeatedly for drop-ship customers. The app worked as advertised in the beginning but some complex customizations we developed presented conflicts that prevent the app from processing correctly via the API to our store. We had to uninstall it. While it wasn't a perfect solution (doesn't prevent the default from changing but does change it back quickly) we ended up developing our own private app solution utilizing Hubspot's "operations hub" to basically do the same thing this app was doing but it works around the code conflict we introduced to the equation. For a more simple store code ecosystem this app should do the trick. What we really need is for shopify to understand that "default" means it doesn't change every time a customer ships to a different address. There is simply no way to "lock" it like in every other ecommerce system.

Our customers were having trouble placing orders because the default address on thier account was defaulting to the last address they entered (usually thier customers address). The app does just the job by making sure our customers feault address is always showing when they come to place orders.