In EASA country, the 350 is one rating with the 300 and 1900.
The 200 is one rating with the 90,99 and 100.
AFAIK there is no credit for B200 time if you do a 350 or vice versa.
The 90-200 is a classrating, the 300/350/1900 is a typerating. (acc.JARFCL).