I don't know anything about the V1–V2 primers, but this sounds a bit like the situation with the V3–V4 primers (see this forum post). I think if you named each of the V3–V4 primers based on where their 5' end nucleotide binds in the E. coli genome, they'd be 341F/805R, but if you named them based on the lowest value position at which any nucleotide of the primer binds in the E. coli genome, they'd be 341F/785R. I'm not sure if there's an agreed-upon convention for primer naming, but in the case of the V3–V4 primers, I've seen both name combinations used. Certainly a tad confusing for newbies like myself!
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