Hi
Gordon,
in the book "Names through the ages" by
Teresa Norman I found these forms:
England:
1154-1603:
Andrew, Dande
1603-today:
Andrew, Dande, Dandy, Tandy
Scotland:
1093-1706:
Andrew,
Andra1706-1850:
Andrew1850-today:
Andrew,
Andra
Wales:
47-1283:
Andras1283-1536:
Andreas1536-1770:
Andrew,
Andras1770-today:
Andrew
Ireland:
1170-1536: Aindréas,
Andrew1535-1650: Aindréas
1649-1800:
Andrew1800-today: Aindréas, Aindrias, Aindriú,
Andrew
France:
768-987: Andrieu
987-today: André
United States:
1620-1845:
Anders,
Andre,
Andrew, Dande, Dandy, Tandy
1845-1945:
Anders,
Andra,
Andre,
Andrew, Dande, Dandy, Tandy
1945-today:
Anders,
Andre,
Andrew, Dande, Dandy, Tandy
Well, nowhere appears the form
Andy... (?) just Dandy and Tandy...
Hope that helps!
Regards,
Satu