Chord Progression in "The Red Telephone" by Love

The song "The Red Telephone" exhibits an interesting chromatic chord progression.

The link to the song: http://www.youtube.com/watch?v=IzkAwCs5bnI

This song is in the key of A minor. It has (excluding the intro) the form AA'ABBAC.

(The A' is referring to the fact that the second A-section is incomplete.)

The A-section is comprised of a verse followed by an instrumental interlude. It repeats three times and reoccurs later in the song.

The verses have the following chord progression:

C*            Am    G     F#     F  F#  D  G    C    G/B  A
III             i         VII   VI               IV VII  III   VII      I

* Technically a Cmaj7.

The intstrumental interludes between the verses have almost the same chord progression except shorter:

Am G     F#     F F#
i      VII  VI

The three A-sections end with a prolonged Cmaj7 chord, and then the song directly transitions to the B-section.

The B-section is composed of the following chords.

Bb      A*      Bb     A*     E     F      C      E    D    C    D    C     G/B  A
II         I          II       I        V     VI    III     V   IV   III   IV   III    VII   I

* These chords are technically Amaj9, but are referred to as A to keep things simple.

The B section repeats twice with a small string interlude in between.

Finally, the C section includes a shift between the parallel major and minor.

Am         A
i              I

This major-minor shift repeats until the song fades out (20 times to be precise).