Duplication of site not available as it's over 100 pages

We have a website that's built in 7.0 and I want to update this to 7.1 and make some other design changes. This will take several weeks/months as it's quite a large site and so I want to duplicate the site so that we can transfer it over when complete. 

However when I've gone to duplicate the site, it's not available as it says the site is over 100 pages. Is there any way around this so that I can duplicate at least part of the site so that I am not starting from scratch and have to reupload all images and content again? 

I really need to work on the site in a staged environment before launching it and so cannot work on the live site and am not comfortable updating to 7.1 on the current live site as I feel everything will need to be adjusted. 

Many thanks 

With site over 100 pages, you can contact Squarespace Customer Care to get help.

Thanks for your reply, unfortunately they have not been any help. Just said that it's not an option they offer but they have fed back my suggestion to their development team. They've further said that I can't even copy across the media library so looks like my only option is to start from scratch or move to a different platform as you can apparently export all content out for something like Wordpress but not between Squarespace sites which is frustrating. 

Hi @NewViewMarketing, I'd highly recommend using this plugin. You can copy pages from 7.0 to 7.1. Still will take some time to make sure everything looks correct. But it will be faster than having to manually copy everything over. 

Thanks for your replies. I went through the pages with the client and there were quite a few no longer needed and so I've managed to reduce the number down thankfully and then duplicated the site. There will be a lot of work involved to get it looking right in 7.1 but as we're redesigning anyway it's saved a lot of copying and pasting.