Blazar is a subclass of active galactic nuclei with a relativistic jet directed roughly towards us. They are characterized by a highly variable emission that spans the entire electromagnetic spectrum from radio to GeV/TeV gamma-ray with strong and variable radio and optical emission. Though they exhibit strong and rapid flux variability, the location of the peaks in their spectral energy distribution that shows a characteristic double-humped structure rarely changes. The BL Lacertae object OJ 287, is peculiar in this regard that it is the very first blazar to exhibit spectral changes that are representative of the entire blazar class. In this talk, I will discuss these new spectral changes which have mostly appeared around the expected ~12-yr recurrent flares, its implications on exploring and understanding highly powerful relativistic jets, accretion physics, and the models of the recurrent outbursts.