Unchecking "Store a copy of all originals..." attempts to move files to computer hard drive

I use Lightrom CC. I have about 500GB of photos. My laptop (Macbook Air) hard drive does not have that much space on it (256GB). For years, I have had the "Store a copy of all originals to the specified location" and had an external hard drive selected. Up until now, everything has been fine.

I bought a new iMac and also a new external (1TB SSD) to use exclusevly for Lightroom backups. I installed Lightroom on the iMac and selected the "Store a copy..." option and now there's a copy of all my photos on the SSD. That all worked fine.

Here's the problem. I *deselected* the "Store a copy..." option on my laptop because I plan on using the space on the other hard drive for something else. After doing this, every time I re-open lightroom on my laptop, it attempts to move all of the photos from the external hard drive back to my laptop. It fills up my laptop hard drive and then says there's no longer enough room. I don't need a copy of all of my photos on my laptop or even on the old external hard drive anymore, and I certainly don't want my laptop hard drive full. I plan to do most of my editing from now on on my iMac, but I still want the option of using Lightroom on my laptop. Sooo, what's the best way around this? Should I delete the folder that has all the backups on my old external hard drive? Delete and re-install lightroom on my laptop? Would doing any of this have an adverse reaction on my photos that are in the cloud? Again, all of my photos are backed up on my new external hard drive. But, now, they are also partially backed up on my laptop and partially on the old external hard drive. 

Thanks for any advice!