By Reuters Staff (Adds detail and background) PARIS, May 19 (Reuters) - Solutions 30 on Wednesday said it would issue a business update on May 21, not May 25 as planned, after France’s AMF market regulator called on the technology services group to publish its results. Shares in Solutions 30, which is headquartered in Luxembourg and listed in Paris, have been suspended since May 10. The company, which has a stock market value of around 1.1 billion euros ($1.4 billion), has filed a defamation suit against hedge fund Muddy Waters in response to a critical report by the short seller, which has a position betting on a fall in Solutions 30’s share price.