Inflation will very likely return to target after a year without further action. Of course, not all policy decisions are so easy. They become harder when the shocks are large and persistent, or when there are multiple overlapping shocks. It is also not always straightforward to determine, given data lags, if inflationary pressures are broadening.
There are no definitive sources you can trust for early warning. At the same time, it can be dangerous to wait too long for perfect information because delays can make the problem Page 3 of 8  worse. Furthermore, it is never clear how much credibility one has until you have lost it.