Fixed 'Updating' that was stuck, now re-uploading all photos??

Hey gang. Kind of a bizarre issue here, but here it goes.

Basically, I had a HD crash... the HD in question was an external that had my enormous photos library. The good news is that I had a backup, so I installed the new drive, named it the same as the old one... everything seemed to be fine.

However, the problem is that my photos app was halfway uploading ALL my photos to iCloud. I say I have about 70K photos.. and it got through 45K or so before the crash.

Once I put the new drive in and opened the Photos app, it got stuck on the 'updating' issue presented in a previous thread here. So, I tried to sign out of iCloud from the system preferences in hopes to just restart everything, but I couldn't even do that! Photos was 'stuck' on in the iCloud system pref pane. Basically, I force quitted all instances of iCloud from the activity monitor... which allowed me to sign out. I signed in again, and everything seemed to work.

HOWEVER, it's re-scanning ALL my photos from my photos library and will start re-uploading them all again???

I'm not sure what to do, because I have a zillion albums that are already in iCloud with half of the uploads done... and I find it hard to believe that iCloud doesn't re-scan what it's already uploaded so that it can start from there and move forward? I already purchased 200GB of space, and it's telling me now I don't have enough space because it has to do everything all over again.

My only option (I guess) is to delete everything out of the iCloud photos library on the website (iCloud.com), and re-sync??? Now I'm worried I will lose photos.

Not sure what to do.