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A page that contains blog posts cannot be migrated as BigCommerce API’s currently does not support any ‘Page Type’ with the attribute value ‘blog’. At present, blog-type pages can only be created in the Store Control Panel. This holds true, even with the new Page Widgets API
Please refer to the following url → https://developer.bigcommerce.com/docs/rest-content/pages
Additional note (Feb-2025): BigCommerce recently made a change so that a web page with the type of "blog index page" cannot be changed to a different web page type. This operation was not supported in the BigCommerce Control Panel and now its also prevented it via API.
‘The url is duplicate’ API notification from the API (Pages, Categories and Products)
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