Thulium, a member of WorldOfCoins, is also “collecting” variants, but he doesn't document them, so whenever I see some of his findings, I do it, to make Numista members (at least those on the English site) informed.
It appears I have one of these Spike/Spur in shield 1922 threepence varieties, I can't seem to find nearly any info about it online. Anyone else perhaps?