Aura H2O Question for those who have 2000+ books

Hi
I have a few questions. I have just over 2000 books how long should your device take to "process content" the first time you are loading books ?

Is it normal to take that long every time you switch on the reader? if not how long should it take?

Im using calibre but my books keep disappearing on the reader.

Thanks in advance ive had nothing but trouble getting books on this damn thing so confused :help: