Where one hadith has two qualified routes, one graded hasan and another sahih, the labels may appear together as a description of its differing isnads.
Suppose chain A contains an upright but somewhat less precise transmitter, while chain B consists of transmitters meeting the stronger precision standard. Both satisfy continuity and the other relevant conditions. Chain A may be hasan and chain B sahih, explaining why both terms can describe the overall report.
The wording is not justified merely because a report has many purported isnads. Their actual technical grades must first be established.