Thanks for explaining your situation so clearly. It sounds like about 150 of the photos you took on your old iPhone 6S are stuck and won’t upload to iCloud or send through AirDrop, Messages, or shared albums. Even though most of your photos synced correctly, these specific ones are likely stuck in a “preparing” state, meaning your phone hasn’t finished processing or uploading them. That’s why you’re seeing messages like “Preparing iCloud link” or not seeing any photos at all when you try to send them through Messages.
This usually happens when the phone wasn’t on a strong Wi-Fi connection, or it didn’t have enough time or power to complete the upload. It’s also common with older devices like the iPhone 6S, which may struggle to keep up with large uploads. As a result, the photos exist on your phone but haven’t made it to iCloud yet, and the system doesn’t know what to do with them.
To fix this, first connect your iPhone 6S to a strong Wi-Fi network and make sure it’s plugged in or fully charged. Leave the phone on and unlocked for at least 30 minutes to give it time to finish syncing the photos to iCloud. Go to Settings > [Your Name] > iCloud > Photos and make sure iCloud Photos is turned on. If it already is, try turning it off and back on to refresh the sync. Also, check that “Optimize iPhone Storage” is turned on — this can help free up space and allow uploads to continue.
You can also open the Photos app and try tapping on the stuck photos. Sometimes just viewing them helps trigger the upload. If that doesn’t work, try making a small edit — like cropping the photo — and saving it. This can refresh the photo and prompt it to re-upload.
If AirDrop isn’t working, make sure Wi-Fi and Bluetooth are turned on for both your iPhone 6S and the device you're trying to send to. On your newer iPhone or Mac, set AirDrop to “Everyone” or “Contacts Only.” Then, restart both devices and try sending one photo at a time instead of a large group.
If nothing else works, try connecting your iPhone 6S directly to your Mac using a charging cable. Open the Photos app or the Image Capture app on your Mac and see if the stuck photos appear. If they do, you can import them straight to your computer, which avoids the need for iCloud or AirDrop.
Most importantly, don’t delete the photos from your iPhone 6S until you’re sure they’ve been safely backed up or transferred. You don’t want to accidentally lose any special memories from your trip.