“…The observational features that have made OJ 287 unique and untypical blazar are the claim of a persistent quasi-periodic ∼ 12-yr signal in optical bands (Sillanpaa et al, 1988;Dey et al, 2018;Laine et al, 2020), a yearly quasi-periodic variations in the location of quasistationary knots seen in radio images (Britzen et al, 2018) as well as claims of ∼ 22-yr (Britzen et al, 2018) and ∼ 30-yr periods (Cohen, 2017), and many transient spectral features like a sharp break in the NIR-optical spectrum (Kushwaha et al, 2018a, an extremely soft X-ray spectra dominated spectral state (Komossa et al, 2017(Komossa et al, , 2020 with a broadband spectrum similar to presence of an additional HBL-like emission component (Kushwaha et al, 2018b and peculiar timing trends untypical of blazars (Kushwaha et al, 2018b;Komossa et al, 2020;Huang et al, 2021), a Seyfert-like soft X-ray excess state , an iron line absorption feature (Komossa et al, 2020), an spectral cutoff in the high-energy end of the optical synchrotron spectrum (Singh et al, 2021;Kushwaha et al, 2021), etc. Regarding the ∼ 12-yr QPOOs, it should be noted that studies employing diverse and state-of-art timing methodologies (Peñil et al, 2020;Goyal et al, 2018) dispute the ∼ 12-yr recurrent optical outbursts.…”