The de Veres and Belchamp Walter
The de Vere connection to Belchamp Walter is presumably due to the marriage of Geoffrrey de Mandeville (d 1144) to Rohse de Vere
According to Thomas Wright, Alberic de Vere was married to a half-sister of William the Conqueror.
Bishop Odo of Bayeux is well known as William's half-brother. If this is the case then Beatrix de Vere would be Bishop Odo's niece.
The informaiton on the de Vere connection is in addition to what I found in the church guides, originally written by Samuel Philip Raymond.
The Historic England information on Belchamp Hall states that the Belchamp Walter manor "came to John Wentworth" and was then sold to John Raymond I in 1611. This condenses a large period of time to a very short sentence.
What Thomas Wright said: