The question itself will have to be asked of technical support for the manufacturer of the fire alarm system because every manufacturer is different.
My personal experience may help. With the manufacturer I'm most used to, they can automatically assign the devices to addresses, and the leave it up to the programmer to label the devices.
I have found problems with this automatic addressing by fire alarm control panels. The issues that occur become much greater as the fire alarm system becomes larger than the very smallest ones. The issue is in the assigning of location labels. Because each building is different from any other building, labeling the locations for the firefighters has to be done manually; the labels have to be assigned to the proper address.
With a very small system, say a total of 10 devices in the whole building, assigning a label to each automatically addressed device isn't hard. Example: figuring out which device address is going to be labeled "Smoke 1st Floor Elevator Lobby" isn't a big issue when there are only five other smoke detectors to look through in the whole system.
A medium size system, say 100 devices in the whole building, is more difficult. There may be 60 smoke detectors to look at to figure out which address is going to be labeled "Smoke 1st Floor Elevator Lobby". Once that is done, there are only 59 addresses to look through to find out which address is going to be labeled "Smoke 1st Floor by Apt 101". Then 58 addresses, then 57 addresses, and so on.
A larger system, say 1000 or more devices in the whole building, is almost impossible to find the automatically addressed device to assign it a label.
With a small system, I've found that manually addressing the devices is just as easy as automatically addressing devices. On any system that's larger, I've found that manually addressing devices is far easier than trying to save any time or effort using the automatic addressing.
For me, just to be consistent, I always manually address the devices, it's easier.