Can't access my iphone after accidentally restarting when it was preparing for autoupdate...

Then that’s all you can restore.

Did you enable iCloud sync on the phone by going to Settings/your name]/iCloud and turning on the sync switches? If you did you will find any content you enabled by going to https://icloud.com and logging in with your Apple ID.

Sorry, but backups need to be done before you need them. Are you sure you didn’t enable automatic nightly iCloud backups? Are you sure you didn’t do ANY of these ways of preserving photos and videos?

• Archive or make copies of the information you store in iCloud
• emailed, texted or messaged the photos to friends or family
• iCloud photo sync
• iCloud backup
• iTunes backup
• Transfer your photos to your computer via USB cable
• Apple Photo Stream
• Sync to Google Photos
• Sync to some other photo archiving service such as Shutterfly
• Sync to Dropbox
• Sync to box.com
• Sync to Microsoft OneDrive
• Sync to Amazon Photos
• back up to Livedrive
• Backup to any other backup or archiving service

If the answer is no to all of the above your photos are gone forever.