This study examines the effects of underlying voicing in word initial and medial stops on f0 at the onset of the following stressed and unstressed vowel (CF0), respectively, in Standard German (SG) and West Central Bavarian (WB). As opposed to SG, WB hitherto did not contrast fortis and lenis stops by VOT, but the importance of this cue increases in younger WB speakers. The replacement of VOT by f0 as acoustic cue in connection with voicing mergers and tonogenesis is well-studied but not the emergence of CF0 effects together with an evolving VOT contrast. An acoustic analysis of twenty SG speakers as well as ten older and ten younger WB speakers showed higher f0 after fortis compared to lenis stops in SG but only in initial position where VOT was much longer. Younger but not older WB speakers showed signs of developing CF0 effects in initial stops as found in SG which may forecast VOT differences in this position at the population level possibly due to speaker-specific cue enhancement.