Adds low priority restrictions

Author: aturner-epcc

docs/user-guide/scheduler.md

@@ -231,7 +231,7 @@ lists the active QoS on ARCHER2.
     | short      | 32                 | 20 mins      | 16           | 4            | standard     | |
     | long       | 64                | 96 hrs       | 16          | 16           | standard     | Minimum walltime of 24 hrs, maximum 512 nodes in use by any one user at any time, maximum of 2048 nodes in use by QoS |
     | largescale | 5860               | 12 hrs        | 8           | 1            | standard     | Minimum job size of 1025 nodes |
-    | lowpriority | 2048               | 24 hrs        | 16           | 16            | standard     | Jobs not charged but requires at least 1 CU in budget to use. |
+    | lowpriority | 2048               | 24 hrs        | 16           | 16            | standard     | Jobs not charged but requires at least 1 CU in budget to use. Only available to UKRI-funded projects. |
     | serial | 32 cores and/or 128 GB memory   | 24 hrs        | 32           | 4            | serial    | Jobs not charged but requires at least 1 CU in budget to use. Maximum of 32 cores and/or 128 GB in use by any one user at any time. |
     | reservation | Size of reservation  | Length of reservation       | No limit           | no limit           | standard   |  |
     | capabilityday | At least 4096 nodes  | 3 hrs        | 8           | 2            | standard     | Minimum job size of 512 nodes. Jobs only run during [Capability Days](#capability-days) |
@@ -2299,6 +2299,10 @@ other, higher-priority, jobs cannot be run. Although low priority jobs are not
 charged, you do need a valid, positive budget to be able to submit and run low
 priority jobs, i.e. you need at least 1 CU in your budget.
 
+!!! note
+    Low priority access is only available for UKRI-funded projects. Other projects
+    will not be able to use the low priority facility.
+
 Low priority access is always available. Consult the QoS table above for limits on low priority jobs.
 
 You submit a low priority job on ARCHER2 by using the `lowpriority` QoS. For example,