I don't think you can. I think you just lose those coins. So much for their advice to hodl the coin.
The legit thing to do would be to still honor those coins that were purchased or mined by people that supported the project early on. Not sure if they'll do the right thing or just say too bad so sad.
And so if you buy new coins maybe they do the same thing in the future and fork to something else and... "too bad so sad" again
yea the old swap and steal others coins trick isnt new but isnt tolerated on many lvls of crypto, if they think doing thing the uncrypto way will just hurt em.
forum needs to put rules in place for coin swap, Eg old amount of coin must be mined to cover any old holders and only can be used for that. with that that means they cant pull the old u missed the swap date that they tried not to advertise was happening to collect more for themselves