Lightroom cc filling up my iPhone

Update: after completing all uploads, LR app reduced its storage usage from 42GB down to 600 MB!  Not sure why it took that extra space but it's cleared itself up. Thank you all for your input and feedback!

Thanks for your feedback. Let me explain further.

LR settings/stats on my iPhone:

    954GB of 1 TB available cloud storage

    'Only download smart previews' is ENABLED

    I have cleared cache; it shows 0 Gb for cached files.

    'Locally stored copies': 41 GB

    'Free' is 9 GB

    Auto add photos & videos is ENABLED, intentionally

    Cloud status: 'uploading 189 pending (2%)'  and that's because i previously hadn't included videos to auto upload and then selected all local videos to upload, which is in progress.  Photos were already all uploaded.

iPhone stats: 

10.6 Gb out of 256 Gb is free

Disk space usage info:

    Photos: 84 Gb

    Lightroom CC: 44 Gb

Maybe the cache bumped my iPhone to near full capacity (it was around 10 Gb and I cleared it yesterday) but I thought it was copying other pics from the cloud down to my phone.

I dont have any LR albums except one named 'all' which is set to auto import.  It shows 5519 as the counter, while 'all photos' above it shows 5520.  Not sure if that counts photos & videos, or why there's only a difference of 1 when the cloud icon shows 189 pending.

Still, not sure why LR is using 44 GB (maybe that'll lower after the current videos upload is done?).  Perhaps this is the only open item that I'm not clear on.

A couple of things....

There's no selective sync capability, so if you enable LR CC on your phone it will send everything it has (that's not already uploaded) to the cloud, and will download information about all the images in the cloud that it doesn't already know about.

I've phrased that like bit as carefully as I can, because not all the photos are downloaded immediately (and may never be, depending on your settings). First thing that would happen is that all the photo and album information about all new images will be added to the LRCC app on the phone. If you are in the main album screen that download is probably limited to photo counts and album cover thumbnails. If you then open an album, thumbnails of all the images in that album will download, and if you open any single image it will download first a full size preview then either a smart preview or the original (this latter depends on two things: is there an original or only smart preview in the cloud, and what is the status of the checkbox in the LRCC settings>Cloud Storage & Sync tab>Only Download Smart Previews option). But even then that download happens on a per selected image basis, not automatically for all images in the cloud (although there are options to store local copies of the images on a per album basis).

All that's a long way of saying that I'm surprised that LRCC is filling up your iPhone (especially a 256GB model), because you should have sufficient control to prevent that from happening. So first question....exactly how much space has the LRCC app taken up? Next, what's the status of that checkbox in the Settings menu? Have you enabled the Store Locally option on any album? I have 200+GB data in the cloud, the LRCC app on my iPhone uses less than 8GB (and I do have several albums stored locally).

Make sure that Lightroom CC on your phone is actually syncing all your images up to the cloud. For this tap the small cloud icon at the right top. It should say: All synced and backed up. If it doesn't make sure you are connected to wifi and that the sync is running. Afterwards, Lightroom CC should dynamically delete images from your phone to keep enough free space.

Then go to the very main screen and tap the Lr icon. Look at the Local storage icon. t should show you how much of your phone's storage it's using. You can tap the "Clear Cache" button to remove all the cached raw files. It only really needs a few jpeg files and will dynamically download any raw files it needs.

Unfortunately you can't limit which images are available on your phone vs in the rest of the CC ecosystem. They always show the exact same thing on all platforms.

If this happened because you told Lightroom to "auto-add photos" and videos, the only remedy is to uninstall Lightroom from your phone and reinstall it. If you turn on this option and use "Photos in the cloud" for the Apple side, Lightroom will try and import every single image you have ever taken with this phone or any others that are in the apple cloud, not just the new ones. The only way to stop it from doing that is to kill the Lightroom app and delete it off the phone and reinstall it. That's a last resort if that's the actual problem.