What are the potential pitfalls of putting a PhD on hold to be employed by the university? 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 &amp; cons can you see?
I don't know your field, so my answer might be wrong.

It seems to me that taking this opportunity runs the risk of a small lifetime earnings hit (since there's a good chance that it means you would spend an extra year at PD salary rather than TT or industry salary), but that beyond that it would only help you career-wise.  Especially since this year wouldn't count against your clock.  That is, compared to your peers graduating at the same time as you, you'll have more experience, more publications, and experience with more projects.