After the conflict, the C.D. Lealtad was reorganized almost immediately after the obligatory purge of its leaders and players, participating again in the championships of a federation that, since 1941, is renamed the Astur-Montañesa Federation when it took over the clubs of the dissolved Cantabrian Federation plus the provinces of León. , Zamora, Palencia and Burgos. After restructuring the categories, we were stuck in Third Category, classifying in third position in the 42/43 season, which gave us promotion to Second Category. In this division we were fourth in the 43/44 season and Champions in the 44/45, since it helped us to move up to First Category, an aspiration that had lasted for many years and that, unfortunately, the war had ended.
With Ernesto Robledo in the presidency, we were seventh in the 46/47 season and fourth in the 47/48 season, finishing tenth in the 48/49 season. In the 49/50 campaign, which ends the decade, we lost the category by descending for being eleventh. During these years the council, made up of several localities, is no stranger to the growth of football and as a result of the involvement of its inhabitants, other associations such as the Astur de Quintueles Club were born, which starts in the 48/49 season from Third Category in a year where the constitution of numerous clubs throughout the region is facilitated.