Someone on the roll of arms registered X, why can’t I?

Normally in such cases, the registration occurred quite a long time ago.  In fact it might even be before your submitter was born.  Back then the College of Heralds knew a lot less about period heraldry, but in the intervening time it has learnt better and these combinations are banned until such time as evidence that medieval heraldry ever used them is found.

And to be quite honest, if evidence hasn’t been found yet, the odds are pretty slim that it will ever be found. So you can find Gendy flowers, chasing, Piping beasts or the like registered on quite old devices, as these are registered forever, but can’t use them on a new device.

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