You need to consider:
- what are your long term career plans? Is a PhD crucial for that?
- how stable/permanent is the job? Do you risk being made redundant in 6 months time?
- Why does your PhD bore you? Wrong question? Unstimulating environment? Lack of autonomy? Mismatch between personality type and work type? Is the boredom fixable?
There is no universal experience with regard to how year 2/3 compares with year 1. It's hard to say without knowing more about the circumstances.