Part time PE analyst during MFin

Over this summer I have worked as an analyst for a London based PE family office. There did not seem to be a possibility to continue working there when I started, as I was the only intern, and the youngest person in the office was late-twenties with an extensive banking background. So I applied for, was a granted admission and accepted an offer for a MFin here in the city. However, they are telling me that they are very pleased with my work and that the deal team and upper management found me very useful. They have therefore offered me a part-time position next to my MFin, and told me that "I don´t need to worry about work when school is over".

the work I have been doing this summer is finalizing/formatting IC documents, modeling and market/country/business research. I have always been curious and especially enjoy the research part of my work, as well as every chance I have to work at live deals. They have also specified that they want me to put my school work over the work I do for them and that I will be staffed with long-term projects without tight deadlines.

Has anyone here been part of a similar setup, or been in the same position as I am now? How much work can i expect between both school and work? I have yet to sign the contract, which I will receive early next week. I am therefore not sure about total hours a week I will work. I have also wondered if I should pursue IB work before going into PE, not sure if I will be at a disadvantage compared to others since I will not have the training/experience you get from IB, which most others in the field have.