Fire Rated Lobby When Connected to Corridor?

We have a dormitory project where, on the first floor, and entry lobby at the front entrance connects directly into a main corridor that runs the length of the dormitory. On either end of the corridor are exterior exits. There are also exit enclosures from the two upper levels that discharge to the exterior on both ends of the building. This project is under NFPA 101-2018 and is fully-sprinklered.

NFPA 101-2018 7.1.3.1 and 28.3.6 state the following:

7.1.3 Separation of Means of Egress.
7.1.3.1 Exit Access Corridors. Corridors used as exit access and serving an area having an occupant load exceeding 30 shall be separated from other parts of the building by walls having not less than a 1-hour fire resistance rating in accordance with Section 8.3, unless otherwise permitted by one of the following:
(1) This requirement shall not apply to existing buildings, provided that the occupancy classification does not change.
(2) This requirement shall not apply where otherwise provided in Chapters 11 through 43.

Because this is a new dormitory, Chapter 28 also applies:
28.3.6 Corridors.
28.3.6.1 Walls.
28.3.6.1.1 Exit access corridor walls shall comply with 28.3.6.1.2 or 28.3.6.1.3.
28.3.6.1.2 In buildings not complying with 28.3.6.1.3, exit access corridor walls shall consist of fire barriers in accordance
with Section 8.3 that have not less than a 1-hour fire resistance rating.
28.3.6.1.3 In buildings protected throughout by an approved, supervised automatic sprinkler system in accordance with
28.3.5, corridor walls shall have a minimum 1∕2-hour fire resistance rating.

Our question is - is the lobby, by code, considered part of the corridor (and therefore need to be rated)?

Two ways of looking at this - one is that the code is strictly only discussing requirements for the corridor and not a lobby. The other way of looking at it is that the lobby is acting as the corridor when it serves as part of the exit access for the building. 

Normally a 1/2-hour rating wouldn't make all that much of a difference, but there's storefront in the lobby space between an adjacent office and the lobby which would have a cost impact to the project.

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