Moving admin folder to sub domain

I have a problem with Cloudflare and his 100-second timeout. I have come on the idea if I move admin area to a subdomain and exclude subdomain from Cloudflare I will pass that 100-sec timeout. The problem is when I importing or refreshing stock of suppliers products this take more than 100 seconds and I need to manually pause my site on Cloudflare for that time. Is that even possible? If someone has that experience it would be nice t know. I use woocommerce on this site.

Kind regards.

David