Hey @guidegirl,
Thanks for reaching out to us on this!
My first guess is that the script is timing out due to server constrains. Can you try to set higher values for PHP max_execution_time and memory_limit config options?
If you are not sure about how to change those please contact your hosting providers on that.
How many pages is it capable of checking without timing out?
I think there’s no limit to it other than resources and time for the script to process the import.
Please give the suggest recommendation a try and let me know,
Best,
Nico