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Thanks again Marie! You've been really helpful, and it's much appreciated. Unfortunately, we've still not found anything that could cause the issue. That thread shared was really interesting, but their problems was quite different to ours. They lost traffic immediately after moving their hosting, whereas our client lost traffic 2-3 weeks after moving server. I'm still not ruling out the possibility that this could've been the catalyst that set off the big drop. We're stumped; but still dedicating time into solving this issue. I'd love to drop the client's URL in here but I'm sure they wouldn't appreciate us sharing it in this way. The only alternative would be to DM it to someone who knew what they were talking about.