Just my first experience flying on LOT last week:

I flew LO779 (WAW-VNO) on August 12 and I was upgraded at the gate (I was connecting from LO412 from ZRH) to business class (1A). Let's call it a half upgrade as a gentleman was probably also "upgraded" (Eco full?) and sat next to me. So no empty seat next to me (Embraer-190). Cant' complain as I had the business class meal and the flight is under 1h.

I was again upgraded at the gate on my return flight (Aug 21) from TLL to WAW on LO786, to 2A. Eco was not full. This time it was a "real" business class experience, no one sitting next to me. There were just 2 passengers in C, in row 2.