I say, and with Allah's success: She should resume, and the continuity is interrupted; because this amount of continuity is within her capacity. Unlike if she vowed to perform i'tikaf for a month and menstruated, then she does not resume, and she makes up her days of menstruation and connects them to the month so that the continuity does not break. Refer to: Al-Mabsout 3: 121, and Allah knows best.