Has anyone experienced Ischia and/or the Amalfi Coast and/or Portofino in Late September and October? Are restaurants and shops open?
Not first hand but have read many reports--you don't need to worry until late October.
I visited the Amalfi Coast in Nov and had no issues. I did not take a ferry which would have been nice but it's likely ferries will be running on a reduced schedule.
Ischia is an island heavily populated with locals so no need to worry there. I can't imagine Portofino being much different in late Oct. Oct is a nice time to be in IT.
My wife and I stayed 5 days on Ischia at the end of September and early October 2019. The tourist scene was winding down but shops and restaurants in Ischia Porto were still open and the weather was great. The local buses were still crowded, though. We had a wonderful time and hope to revisit the island before long.