Cerdic dies and Cynric takes over, Cerdic possibly dies while supressing the Isle of Wight which is then given to Stuff and Whitgar. The island is probably known as Wihtesea initially but then becomes known as the Isle of Wight.
Anglo Saxon Chronicles - 534AD - Isle of Wight given to Stuff and Wihtgar
Map showing the Battles of the West Seaxe (Wessex)
Map generated using Google My Maps 2024 - showing the Landscape, modern Counties and sea in 455AD
Please Note: this map is my interpretation of the Anglo Saxon Chronicles entries relating to the West Saxons and a number of their kings and their takeover of Hampshire and Wiltshire, the thick purple line shows the modern county boundary. The kingdom of the Suth Saxons are shaded in purple, the great Forest of Andredsweald is shaded in green.
The logic for the coastal changes and the Forest of Andredsweald can be viewed on the following pages:
The above timeline is valid according to the Anglo Saxon Chronicles, however the description of the events is my interpretation of the Chronicles, please read the individual links to see if you agree with this.