@girlonthenet I believe it's this:
https://fullfact.org/economy/side-hustle-reporting-ebay-vinted-income-not-new-tax/
"The new rules about data sharing will mean that digital re-selling platforms now have to automatically pass on data to HMRC if you’re selling 30 or more items or have total earnings over €2,000 (£1,725)."
For the purposes of ecommerce I assume Patreon etc is "casual services" rather than selling physical goods.