Should I quit work to study for an exam?
A: No.
A lot of doctors ask if they should take a career break to study for IELTS or PLAB 1. The answer is no. Because these are easy exams and can be managed easily with a job.
Even for comparatively challenging exams like MRCP 1, it is ideal to not take any career breaks and to study for the exam along with the job.
In the UK, it is not considered justified to take career breaks for exams. So if you tell a consultant during a job interview that you took a 6-month career break to take PLAB 1 or MRCP 1, it will make a bad impression. Because junior doctors in the UK pass their Royal College exams along with full-time jobs. IMGs do the same in the UK because taking a career break on Tier 2 visa is not possible.
Since you have to pass your Royal College exams in the UK along with a full-time job, it would be better to get used to this with less challenging exams (IELTS and PLAB 1) in less challenging environments in the home country.
Lesson: please do not take career breaks to study for exams.