@Jonathon @olivierlambert If it is not being blocked, then it may be their efforts to prevent node saturation by moving from node to node. What plan are you on, is it the free one?
If so then this movement will occur more frequently as they move from node to node roughly around every 5-10 minutes. So will experience this loss (timeout) of connection on a regular basis! With a paid plan its much less frequently, also the Cloudflare ZT support team with detailed logs may be able to aid in stabilising connectivity.
https://community.cloudflare.com/t/my-remote-users-drop-at-least-5-times-a-day-randomly/474817
https://community.cloudflare.com/t/cloudflare-ssh-proxy-dropping-connections/397306
Their minimum paid plan with 100% uptime and SLA is the "Pay-as-you-go" plan. So if your going to be carrying out actions in XOA regularly over a remote connection, which need to have a long timeout then a paid plan would pay for itself.