Is there a way to save SKTextureAtlas(dictionary) sprite sheets to disk to read later?

My app uses SpriteKit and requires the use of SKTextureAtlas for performance. However, it uses user-generated content, which means that atlases don’t initialize using bundled images, but instead have to recreate all sprite sheets, leading to long loading times.

Is it possible to save the sprite sheets made from user-generated content to disk so that SKTextureAtlas can load them instead of recreating all sprite sheets upon every initialization?

Is there any alternative solution to this problem? For example, is there a way to dump a bunch of images into memory to use as a texture pool and keep them there until deallocated?