The LIMITED restriction level that allows the user to allocate only a certain number of CPUs and RAM has been around for quite some time already. It was reasonably usable only for post payment plan, though. With v2.108 release in April 2024, automatic mechanism for switching a pre-payment user from LIMITED to CLEAR level was introduced. This makes the LIMITED feature feasible to use in all setups.
LIMITED accounts can create VMs and services only in the limits of CPU and RAM that is configured in admin.
To get the limits removed, user must top up and buy a certain amount of credit. They can do it in one bigger payment or many smaller payments over time. Admin can configure the amount that must be topped up to be cleared of limits.
The option to force a billing account to CLEAR or LIMITED manually is still available. The account will keep this level then regardless of how much have they topped up. If they run out of credit, go FROZEN and then top up to get their balance positive again, the manually set restriction level will also then apply.
Read more from the payment system documentation, specifically the pre-payment flow section: https://warrenio.atlassian.net/wiki/spaces/WARP/pages/46563694/Billing+and+Payment+System+Overview#Pre-payment