Accredo Health ( ACDO), a company that over the past month has twice changed its earnings guidance, disclosed a $36 million charge related to accounting issues, and fired and sued its auditor, still saw its stock rise as much as 25% Monday following at least two analyst upgrades. Accredo lost more than a third of its value last month after lowering earnings guidance because of weakening revenue and accounting problems it inherited from a recent acquisition. On Monday it pushed earnings estimates for the fiscal year back up (excluding the charge), sending shares as high as $18.95, up $4.28. They've since settled back to $18.36, up $3.19, or 21%. Some said the company's explanation for its newfound earnings optimism was lacking. Raymond James analyst John Ransom said he's not sure why there has been so much volatility in the firm's guidance over the last month. "What is different now vs. then, I still don't think is totally clear," he said. Ransom said the company had a "hastily prepared" conference call last month and "probably overreacted" to some shorter-term trends. Back on April 8, the company lowered its profit estimates to a range of $1.20 to $1.25 a share from a previous range of $1.33 to $1.38, saying the company had not made enough visits to doctors, partly because the sales force was distracted by the acquisition of Gentiva. On Monday, Accredo increased its earnings estimates (again, before the charge) to between $1.32 and $1.34 a share for the fiscal year. But management offered little if any explanation about why the numbers have swung so much in less than a month. Although analysts expressed frustration at this, it wasn't enough to keep several from upgrading the stock, saying that sales of higher-margin products appear stronger compared with those of lower-margin therapies, and that the stock is undervalued on the basis of new estimates for 2004.