I am a PhD student in an applied science subject at a UK university, part way through my first year. I have two supervisors: 'A' is a senior professor, and 'B' is a PDRA. Most of my work is centred around a large multi-university project. A is the PI on this project, and most of B's time is spent on it. B and I often work together on the same problems.
B has recently informed us that she is pregnant and will be going on maternity leave next year. By that point I will be a few months into year 2 of my PhD.
A has told me that that there is a possibility that, if I am willing, my PhD could be put on hold for the duration of A's maternity leave, and I could be employed as a RA to cover the work that she would have been doing.
My initial thought is that if this comes to pass, it would be a win/win: It would provide continuity for the project, and give me more experience and more time around the subject before my funding runs out. While the work that I would be doing would be slightly different to my PhD topic, it would be relevant and closely related.
My question is: What potential pitfalls are there here? What questions should I ask if this is formally proposed? What pros & cons can you see?