iOS updates are giving some hard time for GoodTask users at the moment. I'm sorry about inconvenience.
With 4.8.5 update, performance should be improved for the main usage inside the app. If you're experiencing heavy load of delay, it may be due to some indexing of Reminders database that's running under the hood. It should be resolved automatically.
When you edit tasks and go out of the app directly, app icon badge may go away for some seconds before coming back. This is due to some behavior change on iOS 13 but will be fixed on next update.
Next update will be focused heavily on stability and performance with multi-window on iPad and more. I'll do my best to bring it to you soon. Thanks!