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Hi Olivia - Thanks for the question. It's definitely a good one to wrap your head around as anytime you change URLs it's a large undertaking and a lot that can go wrong. What should happen when you move from HTTP -> HTTPS and have done everything correctly (not chaining redirects, etc) is that your HTTP pages will stop ranking in favor of your HTTPS pages which should take their place. Some people have seen a small improvement in rankings from moving to HTTPS, but for the most part people just saw a swapping out of the ranking URL to the HTTPS URL. Make sure you annotate Analytics when this goes live so you can make some correlations from the move. Sometimes people have seen an increase in clickthrough rate because users subconsciously trust HTTPS sites more. Good luck!