The Soviet Area Liberation Stamps come from what in the PRC catalogue is called the Second Revolutionary Civil War Period. So this area, rather than being a geographic area like the other LAS issues, is more a period in time grouping. The First Revolutionary Period is considered to have begun in the late 1920's, and did not develop as strongly as planned. The Second Period covers the revolutionary base areas which were very fluid and changed on a day's notice depending on the pressures brought by the Guomindang (aka Kuomintang, Kuomindang). The name Soviet Post was abolished after the Xi'an incident when both major political parties were supposedly cooperating to rid the country of the invading Japanese forces. Also note there were the "Red" issues in different base areas since at this time the communist forces were not all necessarily a cohesive unit. They came together during the Long March, and much was reorganized after their arrival in Yanan. See the map below, taken from the PRC catalogue.
There are 35 different stamps in this area according to the PRC stamp catalogue. The JPS lists 45 stamps. Yang lists 35, Scott none, and Gibbons 41.
This area is not widely collected mainly due to high prices and scarcity. Due to the high prices, extreme caution should be exercised when making purchases of these issues at auction or through dealers, even the most trusted dealers. Note that The China Stamp Society, but few others, have experienced collectors that can expertise in this area.
The Second Revolutionary Civil War Period as
identified by the PRC stamp catalogue.
Page 1.
Notes
The Secondary Revolutionary Period stamps are pretty straightforward and easy to identify, but subject to immitation. There are no overprints known to me at this time. One should be careful of these as catalogue illustrations provide a guide for the forger and unscrupulous. Adding to the difficulty is that many stamps pictured in catalogues in the past are now known to be bogus. Due to their scarcity, many illustrations are used issues with much detail lacking, and some catalogues reproduce (poorly) images from other catalogues.
None of these stamps are encountered often.
You do have to be somewhat careful of the illustrations in all catalogues.
The JPS identified stamps are organized differently from the PRC listings.
The Yang identified stamps are somewhat different from the PRC listings.
No Scott listed stamps fit in this area.
Gibbons calls these "The Early Issues" and lists 41 stamps in that category (Red Posts and Chinese Soviet Republic).