Revised card numbers disagree with Gatherer

I just finally figured out why my card import was showing me strange results, Revised cards don't have the same collector numbers here than on scryfall...

https://deckbox.org/editions/21-revised-edition

Swamp here are:
- 299
- 300
- 301

And on Scryfall they are https://scryfall.com/search?q=swamp+set … ique=cards

- 298
- 299
- 300

I've looked around and I can't quite find the authoritative source for collector ids for these old sets, but that's certainly a discrepancy I figured was worth pointing out.

What happens in my case is that my CSV import has the card numbers looked up from Scryfall, and when importing on deckbox, I guess Swamp/Revised/298 doesn't exist, so the system fall-backs to just Swamp/Revised and merges up these cards with the closest match.

I imagine that for most cards, this discrepancy gets transparently solved by the name fallback, but in the case of basic lands, it does behave strangely.

Thanks for an awesome site!