How to determine required cloud quota & automatic cleanup settings

The following questions relate to a weekly backup of “Entire PC” to cloud.

I understand from a previous forum answer that the first backup would be full and then the subsequent backups would be incremental.

I am trying to determine how much cloud storage I need and how I should set the Automatic clean-up options.

I have just upgraded my storage from 250GB to 500GB, and my first cloud backup was approximately 450GB.

My Activity for my Daily backup (to local disk) shows that, over the last month, the total size per week of the 6 daily incrementals did not exceed 11GB.

Based on the above numbers and on my current understanding of how storage quotas and automatic cleanup work, I have tentatively set the automatic cleanup options as follows:

“Store no more than <n> recent backup versions” = 4
“Delete versions that are older than <n> <days/months/weeks> = Disabled

Could anyone please advise me as to whether these settings should enable me to successfully run this backup without further increasing my storage quota?

Also, what is the meaning of the notification about low cloud space, “Less than 30 percent is free.  You will not be able to use Acronis Cloud soon.”?  Does that mean that the next backup will not work, or does it just mean that eventually it will not work?