The 60-day DL doesn't exist in real life either during the off-season. By rule, all players on the 60-day DL are reinstated from it by the filing date for the reserve lists (which is November 20, if memory serves). So there is only the 40-man roster. If the player is still unable to play come spring then he can be put back on the DL then.
As to what OOTP is doing, hopefully someone can provide an answer.
