The last SB2C reported in squadron inventory was a SB2C-5 with VA-54, 1 Jun
1949. Here are the codes through 1949:

A Anacostia
B Atlanta
C Columbus
D Dallas
E Minneapolis
F Jacksonville (also used by Oakland 1948)
G Oakland
H Miami
I Grosse Ile
K Olathe
L Los Alamitos (also used by Akron 1948)
M Memphis
N Spokane (1948)
P Denver
R New York (Brooklyn)
S Norfolk
T Seattle
U St Louis
V Glenview
W Willow Grove
X New Orleans
Z Squantum

Also in 1946 a second letter was used to indicate squadron type:
A Attack
F Fighter
P Patrol
R Transport
U Utility

example: DA would indicate an attack squadron based at NAS Dallas.
The second letter was dropped in 1948.