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I think it's a great idea to stoke demand by creating blog posts before the product pages are up. If you think about it you're suggesting two options: do nothing or do something. If your product pages won't be up for awhile, might as well put that content to use, which will help you uncover a few things: How difficult is it to rank for product related keyword? How much natural demand is out there for my products already? Are people willing to sign up for a waiting/mailing list for my products? What types of content do readers find most compelling on my site or in my niche? I wouldn't wait because you never know what delays there will be in the future, so might as well start now. Switching platforms, such as to Shopify, is always a pain, but if you're going to be migrating pages anyways, a few blog posts won't be a huge technical challenge. Possible SEO consequences/recommendations between blog posts and product descriptions: They are two different things. When reading blog posts, people are looking for information, stories, ideas, etc. When people read product pages they want to know details and FAQs about that product specifically. There will be some overlap, but keep the goal of the user in mind. That said, you can use some of the product descriptions within blog posts, but I wouldn't just copy/paste. There's no such thing as a duplicate content penalty, but it's usually not a good idea to replicate pages across your site word for word. When you write blog posts about your products, link to the product pages from within the post. You always want to prioritize product pages for your money keywords, and blog posts for more informational/long-tail/high volume, but low difficulty keywords - two different strategies. Hope that helps! Let me know if you have follow-up questions!