It was outside from the beginning, that is how it was grown at the nursery. They were keeping all their plumies outside for what I could see.
So getting yellow leaves is not a common occurrence? It already scares me. I fed her Osmocote slow release about 2 weeks ago maybe, and I used less than it was written on the bottle for that size of pot. If you think it's too much fertilizer anyway, I could remove the upper soil and replace with new one, with no fertilizer. The nursery guys told me they use only water soluble fertilizer each time they water them.
On the other hand, I don't know for sure what the soil mix is in the pot, it's mulched and I can't see through it. When I water it, water comes out the bottom pretty well, like it does from my cycads pots which I know for sure have a very good drainage mix.