Believe we are accurate in placing the marriage as "before 11 May 1646," as that is the date given by Walter Goodwin Davis (and further referenced below) for a letter her father, William Bisby, wrote to his sister-in-law, Mary Wyllys, then wife of Gov. George Wyllys.* About Phebe, William Bisby then wrote, "shee was rash in her first marryage, & soe in her second."
References--
(1) Citing "Connecticut Historical Society Collections, XXI: 87-90 ..," Walter Goodwin Davis, "Ancestry of Thomas Bressey of New Haven, Conn.," New England Historical and Genealogical Register, 112 (1958):27-44 at 42-43 (6-Thomas Bressey); digital images by subscription, AmericanAncestors.
(2) William Bisbey (London) to Mary Wyllys (Hartford), letter dated 11 May 1646 in Albert C. Bates, Lemuel A. Welles, Forrest Morgan, eds., ''The Wyllys Papers ... 1590-1796'', as Collections of the Connecticut Historical Society, 31 vols. (Hartford, Conn. : Published for the Society, 1860-1967), 21 (1924):87-90 at 89; digital images, HathiTrust.
*Note: According to her profile, Mary Smith married (1) Alexander Bisbey, and was his widow when she married (2) George Wyllys. According to Davis, Alexander Bisby was William's brother, see Walter Goodwin Davis, The Ancestry of Sarah Stone ... (Portland, Me., The Southworth Press, 1930), 115-122 (Bisby) at 118-119 (5-Alexander Bisby); digital images, HathiTrust.