The Army policy on accelerated promotion is being updated.
The new regulations will be live from 01 July for Regular and Reserve
personnel and come into effect from the 2020-21 annual reports.

Soldiers graded with a potential recommendation of “exceptional for promotion one rank up” in their annual report, short tour or duty period report and special circumstance report will be considered for early promotion if they have completed the military training and education required for their current rank.
No other cap badge policy, processes or restrictions will be implemented in
addition to this policy.
For more information search for ABN 071/2020 on Defence Connect.
Reference
Soldier (2020) Promotion Policy Changes are in the Offing. Soldier: The Magazine of the British Army. June 2020, pp.16.