The rules haven't changed, simply the amount of regiments willing/able to play have. In the old days why this was less of a problem was if there was say 20 sign ups the 4 regiments that looked 'dodgy' or were 'less old/reliable' would not be accepted and the other 16 would. In this case it doesn't even look like we are going to reach the 16 sign ups that we have in every other addition so there are less choice. The rules are the same it's just the amount of regiments to choose from that has caused this 'flaw' within the rules meaning that it is what it is essentially.
If there was a sudden influx in regiments that were long standing/active regiments then sure I'd be happy to accept them over both K-KA and 2eFus as they would be the 'pedigree' as such for this tournament.