Shorter than Edward VI. Perhaps the shortest of all... Edward VIII was never coronated.
The five shortest reigns were
1. Lady Jane Grey (9 days)
2. Edward V (78 days)
3. Richard III (2 years, 57 days)
4. James II (3 years, 309 days)
5. Mary I (5 years, 121 days)
Charles the III would become # 4
The list is missing Edward, VIII He should be # 5.
https://royalcentral.co.uk/features/the-shortest-reigns-in-english-royal-history-172147/