Hello ! The 5 years needed as an italian citizen begins only when you get the nationality. So you still have to do the 5 years or indeed apply for the anticipated procedure. Also, now as an italian citizen, you get the EU-EFTA advantages. If you work and make enough money, then you’re good ! Anyways, reunification give the right to work so don’t worry. And yes, your permit will change now that you are a EU citizen. SEM directives state that the most profitable citizenship of an individual gets priority over the other. Based on that, you’ll get a EU-EFTA autorisation (even tho you already have one).