Egyptian Walking Onion Varieties?

Are there varieties to walking onions?

I own an walking onion that produces red topset bubils. I have heard mention that there might be a white bubil variety out there? Are there more variations possibly?

I'm on a quest to accumulate multiple types of  perennial alliums so this is a potentially exciting development.

I grow two un named walking onions with different coloured topsets - one with a reddish tinge and the other yellowish coloured.

They have only just started to emerge so the topsets are a few months away yet.

Here are photos from several years ago.

Some plants produced two tiers of topsets, with both flowers and bulbils and I made a half hearted attept to produce seed by removing the bulbils but was unsuccessful.

You could get the white ones Southern Exposure Seed Exchange.

Mine have always been the red-topset kind but I've noticed the two-tier thing Megan mentions too, never managed to get seed from them either, the bulbils always seem to win. Would be curious to grow a white one alongside and see if there's any taste difference between them.