I have not come across quarterly reviews for someone in a PAYE job with a stable income and it is also unusual for CF to do anything they don't need to. I would ask them why. But, at the end of the day, you have to comply with all reasonable requests and monitoring income is reasonable. Some other IPs request all payslips, although this is overkill as the P60 provides all they need and the latest payslip will give a running total.
I suspect this is to catch pay increases earlier than is traditionally done.
My opinions are merely that .. opinions based on experience. Always seek professional advice.
IVA Completed 23rd July 2013 .... C.C. 10th January 2014 http://foggy.blogs.iva.co.uk