I've only posted two identical profiles - I suspect both are from the same source, namely the Squadron-Signal brochure. Which picture are you referring to exactly? The eBay picture fits the "yellow 3" profile well - the tail tip is too bright for red I think.IMHO the pic and the profile you posted above ( I have checked on my copy of the booklet ) don't have anything in common with. Unfortunately the series of the MiF isn't too accurate and provides the general info mostly. What is more, there are profiles that are the authour's wishful thinking often.
PS. the painted tail tip had also the 50 IAP IIRC. But their Migs had the large yellow or white three-digital numbers on the fuselage sides.
The 31 and 15 IAPs were stationed at Kaunas airfield.
IIRC, the tail tips of I-16s from 10 IAP and I-153s from 15 IAP were colored red regardless of squadron number.
I don't know why Massimo Tessitori decided that the tail tips of 124 IAP had different colors by squadrons. But I can't exclude this option either.