Seems related to this issue: https://community.cloudflare.com/t/confirm-1-1-1-1-dot-is-being-used-using-curl/200277
Their customer service gave me the "other users have reported this issue and we're working on it". They couldn't provide an ETA or say how long it's been broken.
Normally I'm accessing it from California, but am now on a Vodafone SIM I bought while here in Italy.