Tutoring in OSS 235 (the MaRC) is according to the following schedule from the first day of classes until the last day of classes.
9 AM - 9 PM
9 AM - 2 PM
6 PM - 9 PM
J-term and Summer Sessions
The MaRC is open with limited hours during summer and J-term sessions, usually on weekdays around midday.
Additional Math 005/006 Tutors in MHC 108: Hours can be found here.