HBO <HBOC> URGES SHAREHOLDERS AGAINST ANDOVER HBO and Co said it sent a letter of strongly urging shareholders not to sign any proxy cards sent by Andover Group. ON March 30, Andover Group, a two-man general partnership which owns about seven pct of HBO's stock, filed preliminary proxy materials with the Securities and Exchange Commission seeking to nominate an alternative slate of directors at the company's April 30 annual meeting. Andover had expressed an interest to acquire the company in September 1986 but HBO has never received an offer from them, it said. In addition, HBO said its financial condition is improving rapidly as the result of a significant restructuring implemented in 1986. It expects the company to report net income of about 40 cts per share in 1987 and a very significant increase in 1988. For the year ended December 1986, the company reported a loss of 3.6 mln dlrs, or 16 cts per share.