His birth index:

Name:                       Mother's Maiden Surname:
WARREN, MICHAEL RAYMOND     BOSANQUET  
GRO Reference: 1928  J Quarter in CUCKFIELD  Volume 02B  Page 201
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I strongly suspect this 1939 Register entry is his at 9 West Downs Preparatory School For Boys & Masters Lodge Romsey Road, Winchester, Hants

First name(s)        Michael R
Last name(s)         Warren
Birth date           08 Apr 1928
Birth day            8
Birth month          4
Birth year           1928
Sex                  Male
Marital status       Single
Occupation           At School
E. D. letter code    EDVY
Schedule             3
Schedule sub number  99
Archive reference    RG101/2360G/013/11
Piece number         2360G
Item number          13
Line number          11
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There are 28 marriages of Michael R Warrens on Find My past from 1988 onwards.  The only hope of sorting that out is to see what his will says, currently unavailable as the site is down for 5 days. (24 Jan 2022)
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His death index on FindMYPast includes the same birth date as in 1939, so they mutually confirm one another:

First name(s)  Michael Raymond
Last name      Warren
Gender         Male
Birth day      8
Birth month    4
Birth year     1928
Death quarter  4
Death year     2006
etc.

And the straight from the horse’s mouth record is, otherwise, in full:

Name:                        Year of Birth:  
WARREN, MICHAEL RAYMOND      1928  
GRO Reference:  DOR  Q4/2006 in LEWES  (4591)  Reg 84D  Entry Number 193
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His probate index:

Will site is Down, can’t order.

But an abstract on FindMyPast gives

Full name:     Michael Raymond Warren
Death date:    05 Nov 2006
Probate date:  07 Jan 2008
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