Except postcards, all stamps with Arabic letters were removed from circulation after May 1, 1934. The last series of stamps published with Arabic letters was the three stamp series from 1929, on which Latin letters and values were surcharged.
The first series in which the new Turkish alphabet was used is the 3rd London series, which went on the market in 1926. If we consider that the letter revolution which adopted Latin letters instead of Arabic was accepted into law on November 1, 1928, within three years, all Arabic letters were removed from new stamps and within 6 years the old stamps were completely removed from circulation.
1926 - 3rd London series - first series with Latin alphabet for Turkish language
November 1, 1928 - Law changing Turkish alphabet from Arabic to Latin
1929 - Last series of stamps showing Arabic alphabet along with Latin for Turkish language
May 1, 1934 - All stamps with Arabic letters removed from circulation