RewriteEngine on
RewriteBase /

# 1st set of rules
RewriteRule source1.html destA1.html [S=1]
RewriteRule destA1.html destA2.html [R]
RewriteRule destA1.html destA3.html [R]

# 2nd set of rules
RewriteRule source2.html destB1.html [S=2]
RewriteRule destB1.html destB2.html [R]
RewriteRule destB1.html destB3.html [R]
RewriteRule destB1.html source1.html


# 3rd set of rules
RewriteRule source3.html destC1.html [N]
RewriteRule destC1.html destC2.html [R]