Where were the "rules" broken? Here's the progression since that 1921-S Lincoln: 1921 Mercury 1921 Morgan 1921 Buffalo 1937 Buffalo 1937 Lincoln 1937 Buffalo 1935 Buffalo 1935 Connecticut Commem 1935 Peace 1924 Peace 1924 SLQ 1917 SLQ 1930 SLQ 1920 SLQ 1920 Merc ....and then someone posted a 1941 Lincoln.
For some reason when I posted ALL of page 239 did NOT display on my computer. So my comments were WAY off. Sorry about that!!! Mercurys or 1920 dated coins are indeed correct at this point in time.
I seem to be having issues with "time" on my computer on this specific thread. I am not seeing posts until significantly later than they've occurred. Hopefully this has straightened itself out by now.