How to add images to advanced gallery?

Hi, thanks for a great toolkit, has dramatically reduced my Gutenberg blocks headache.

I am wondering if there is a way of adding/replacing images to an existing gallery, without having to create a whole new one each time?

As it stands you have to create a gallery by selecting all the images first, but for an ongoing project I want to be able to update the gallery as time goes on rather than rebuild it from scratch each time. Currently when I click the “upload image” icon at the end of an existing gallery it just creates a new gallery and erases what was there before.

If there is a way of doing this that I’m missing please let me know, thanks.

The page I need help with: [log in to see the link]