Here is a list of Rationing Points and Dates during WW2 that I have typed up after much research. My husband and I have been going and continue to go, to our local public library and use their research room to study about the home front during WW2. These are the release and expiration dates to the best of our knowledge from our research.
RATIONING POINTS ARE AS FOLLOWS,
EACH PERSON was given 48 BLUE POINT STAMPS PER MONTH.
BLUE STAMPS were to be used for  PROCESSED FOODS
Such as;
FRUITS AND FRUIT JUICES,
FROZEN FRUITS
DRIED AND DEHYDRATED
CANNED AND BOTTLED VEGETABLES AN VEGETABLE JUICES
OTHER PROCESSED FOODS, CANNED AND BOTTLED INCLUDING BABY FOOD
FRESH FRUITS AND VEGETABLES ARE NOT RATIONED
RED STAMPS
EACH PERSON was given 16 RED POINT STAMPS PER WEEK TOTALING 64 POINTS PER MONTH.
RED STAMPS were to be used for MEAT, BUTTER, CHEESE, LARD, MARGARINE, OILS, CANNED MEAT, TINNED FISH, CANNED MILK, ETC.
Following along here, the dates and stamp letters as they are released for use.
If this seems confusing to you, think about the people in 1943 having to figure out all of this at the grocery store. They found out through newspaper and grocery store posts when stamps were valid and when they expired. Also there were stamp books for sugar and gasoline, coffee, shoes and many more items. In this post I will be posting food. I will post sugar, gasoline, shoes etc later.

The above photo are blue ration stamps from a real War Ration Book Number two.
Rationing of processed foods started March 1st, 1943. In 1942 rationing had started for sugar, gasoline and other goods. In this post I will be discussing Foods.
MARCH 1, 1943   BLUE STAMPS
       A, B, & C VALID   Expire March 31, 1943
MARCH 29, 1943   RED STAMPS
       Letter "A" valid March 29   Expires April 30, 1943
I will use the two top dates to explain. On march 1, 1943 you could purchase processed foods with blue stamps lettered A, B & C. Their books were filled with other letters and numbers but they could not use those letters and numbers until they were released. For processed foods the letters A B & C were released for the month listed. People could purchase their canned vegetables, fruits, juices etc but had to be very careful to stretch these point numbers and letters to last the month.
Red 
stamp that was issued (photo above) March 29, 1943 only released one letter per 
week and at times there were changes on the release dates. So for March 
29 you could go with your letter "A" row and purchase 16 points of food. 
 This was very difficult because in March of 1943 Butter was 8 points, 
Most meat was at least 8 points per pound, cheese was 8 points. Each 
family member received a book of stamps. The less family members the 
harder to get enough stamps to get butter, oil meat etc.
       
APRIL 1, 1943    BLUE STAMPS
       D, E & F Valid   Expire April 30, 1943
APRIL 5, 1943   RED STAMPS
       A & B valid      Expires April 30, 1943
APRIL 12, 1943   RED STAMPS
       A, B & C valid    Expires April 30, 1943
       
APRIL 19, 1943   RED STAMPS
       A, B, C & D valid    Expires April 30, 1943
APRIL 26, 1943   RED STAMPS
       A, B, C, D     Expires April 30, 1943
       E valid April 26   Expires May 31, 1943
APRIL 29, 1943   BLUE STAMPS
       G H & J Valid     Expire May 31, 1943
       ( there was no letter I )
MAY 3, 1943     RED STAMPS
       E & F  Valid     Expire May 31, 1943
MAY 10, 1943   RED STAMPS
       E, F & G Valid   Expire May 31, 1943
MAY 17, 1943   RED STAMPS
       E, F, G & H Valid   Expire May 31, 1943
MAY 24, 1943    RED STAMPS
       E, F, G & H Valid    Expire May 31, 1943
       J Valid       Expire June 30, 1943
JUNE 1, 1943     BLUE STAMPS
       G, H & J  extend   Expire June 7, 1943
       K, L & M Valid   Expire July 7, 1943
JUNE 1, 1943     RED STAMPS
       J & K Valid     Expire June 30, 1943
JUNE 8, 1943     RED STAMPS
       J, K & L Valid     Expire June 30, 1943
JUNE 15, 1943   RED STAMPS
       J, K, L & M Valid   Expire June 30, 1943
JUNE 22, 1943   RED STAMPS
       J, K, L, M, N Valid   Expire June 30, 1943
JULY 1, 1943     RED STAMPS
       P Valid     Expire July 31, 1943
       ( there was no letter O )
       
JULY 8, 1943     RED STAMPS
       P, Q Valid     Expire July 31, 1943
JULY 8, 1943     BLUE STAMPS
       N, P & Q Valid   Expire August 7, 1943
JULY 15, 1943   RED STAMPS   
       P, Q & R Valid   Expire July 31, 1943   
JULY 22, 1943   RED STAMPS
       P, Q, R & S Valid   Expire July 31, 1943
JULY 29, 1943   RED STAMPS
       P, Q, R, S, Valid   Expire July 31, 1943
       T Valid     Expire Aug 31, 1943
AUGUST 1, 1943   RED STAMPS
       T & U Valid     Expire Aug 31, 1943
AUGUST 7, 1943   BLUE STAMPS   
       R S T Valid     Expire Sept 20, 1943
AUGUST 8, 1943   RED STAMPS
       T, U & V Valid   Expire Aug 31, 1943
AUGUST 15, 1943   RED STAMPS
       T, U, V & W Valid   Expire Aug 31, 1943
AUGUST 22, 1943   RED STAMPS
       T, U, V, W Valid   Expire Aug 31, 1943
       X Added     Expire Oct 2, 1943
SEPTEMBER 1,
1943       RED STAMPS   
       X & Y Valid     Expire Oct 2, 1943
SEPTEMBER 8
1943       RED STAMPS
       X, Y & Z Valid   Expire Oct 2, 1943
SEPTEMBER 8
1943       BLUE STAMPS
       R, S & T Valid   Expire Sept 20, 1943
       
SEPTEMBER 15
1943       RED STAMPS
       AND BROWN STAMPS
       X Y & Z Valid   Expire Oct, 2, 1943
       Brown A Valid   Expire Oct 2, 1943
       Red and Blue stamps have been from ration 
       Book number two. Brown Stamps are
       Replacing red stamps. Green stamps will be 
       Replacing blue stamps in new ration book 3.
SEPTEMBER 20   BLUE STAMPS
1943       U, V &W Valid   Expire Oct, 20 1943
SEPTEMBER 22
1943       RED STAMPS
       X Y Z Valid     Expire Oct 2, 1943
       BROWN STAMPS
       A & B       Expire Oct 2, 1943
SEPTEMBER 29   RED STAMPS
1943       X Y Z Valid     Expire Oct 2, 1943
       BROWN
       A B       Expire Oct 2, 1943
       Brown C Valid   Expire Oct 30, 1943
OCTOBER 1
1943       BLUE STAMPS
       U V W Valid     Expire Oct, 2 1943
       X Y & Z Valid   Expire Nov 20, 1943
OCTOBER 4
1943       BROWN STAMPS
       C & D Valid     Expire Oct 30, 1943
OCTOBER 11
1943       BROWN STAMPS
       C D & E Valid     Expire Oct 30, 1943
OCTOBER 18
1943       BROWN STAMPS
       C D E & F Valid   Expire Oct 30, 1943
OCTOBER 25
1943       BROWN STAMPS
       C D E F Valid     Expire Oct 30, 1943
       G Valid     Expire Dec 4, 1943
NOVEMBER 1
1943       BROWN STAMPS
       G & H Valid     Expire Dec 4, 1943
NOVEMBER 1
1943       BLUE STAMPS
       X Y Z   Valid     Expire Nov 20, 1943
       GREEN STAMPS ( From book #4 )
       A B C Valid     Expire Dec 20, 1943
NOVEMBER 8
1943       BROWN STAMPS
       G, H & J Valid   Expire Dec 4, 1943
       ( no I stamp)
NOVEMBER 15
1943       BROWN STAMPS
       G H J & K Valid   Expire Dec 4, 1943
NOVEMBER 22
1943       BROWN STAMPS
       G H J K Valid     Expire Dec 4, 1943
       L Valid     Expire Jan 1  1944
NOVEMBER 29
1943       BROWN STAMPS
       G H J K Valid     Expire Dec 4, 1943
       L & M Valid     Expire Jan 1, 1944
DECEMBER 6
1943       BROWN STAMPS
       L M N Valid     Expire Jan 1, 1944
DECEMBER 6
1943       GREEN STAMPS
       A B C Valid     Expire Dec 20, 1943
       D E F Good Thru   January 20, 1944
DECEMBER 13
1943       BROWN STAMPS
       L M N & P Valid   Expire Jan 1, 1944
DECEMBER 20   BROWN STAMPS
1943       L M N P Q Valid   Good thru Jan 1, 1944
DECEMBER 27
1943       BROWN STAMPS
       L M N P Q Valid   Good thru Jan 1, 1944
       R Valid     Good thru Jan 29, 1944
JANUARY 3
1944       BROWN STAMPS
       R & S        Good thru Jan 29, 1944
I Will do a part two for the food stamps taking it into 1944 as our research continues.
   


