Michel lists the series as "September, 1943". Likely corresponding with Rommerskirchen that said the Tirane post office opened on September 22nd. Erler said the stamps were issued in the beginning of October.
However, the Union Postale (UPO) Vol. LXIX page 20 reports that the Tirane post office was opened on October 23rd, other post offices 10 days later.
These stamps raise the question of what criteria determine whether a stamp issued under foreign occupation is listed as an occupation stamp (i.e., with an "N" designation in Scott). The stamp in the photo is is E3 in Scott - a special delivery stamp. It's an overprint of E1, which was issued in 1940 under Italian occupation and bears the of Italian King Victor Emmanuel. By 1943, the Germans had taken over the occupation from Italy, and E3 was issued under German administration. The same overprints occur on regular issues.