I would like to share a situation that happened to me.
In January I booked a room at the AKL for spring break using a code that appeared on
www.mousesavers.com. I originally booked a pool view room (We've stayed in Savannah view and don't think it is worth the extra, so I wasn't hoping for a free upgrade). I later decided that a standard view was all we needed since we are commandos and mostly use the room for sleep and showers. When we are at the resort we are usually by the pool. Being spring break, I didn't want to cancel the first ressie until I knew that I could get the lower priced room and I didn't want to loose out completely on a room at AKL (it is our favorite resort at Disney).
Since my deposit had already been charged to my credit card and the confirmation mailed out, they switched me to AKL and I handled the change with the reservation person at the front desk (or where ever they keep him, lol). He asked all of the same questions the CRO asks, i.e. how many in party, names and ages of children, date of arrival, date of departure, etc. I don't remember, but I think he just changed the reservation in their system and I received a new confirmation with the lower rate and it showed that the deposit had been made at the higher rate and my amount due was the new total less this deposit. The confirmation number was the same.
When the AP rate came out, it was less than the code rate was. Under the same logic, I tried to make a new reservation at the AP rate at the AKL for the same dates. The CRO saw that I had a reservation already for those dates and transferred me to the supervisor who read all of the information to me about the first ressie and about the change to the standard rate and the date the change was made. He told me he would have to transfer me to the reservation person at the AKL to make the change. Then I made the change without having to cancel any reservation at all.
The reservations agent at AKL said that in the past you had to cancel one ressie and book a new one to make any change and that you formerly could have two ressies for the same dates, but now you could just change the rate of the original ressie without having to make a new one. He said that this was to pervent the hastle of making a new ressie and being charged a second deposit and then canceling the original and being refunded the deposit on the original. I think it is probably a cost saving measure that Disney doesn't want to pay the service fees to MC or VISA twice for the two charges and then pay a service fee for making a refund (if there is one). Anyway, it makes more paperwork or e-paper work for them.
In short, it looks like under this new computer system, you can make a ressie at whatever rate is available and change the rate to whenever a lower rate or better code comes available. You just don't get refunded the difference between the original deposit and what it would be at the new, lower rate.
My guess is that the OP's CM meant was that since Luvinit was a FR, he or she could book at the FL rate and change it later if a better rate came out or if the AP rate was better than the Fl rate.