In order to attack a Core 1 POB it is now required to post a notice in the Attack Declaration Thread as was already the case for Core 2 and higher bases. Unlike Core 2 and higher bases it is not required (though encouraged) to have forum RP with the base owners prior to the attack. Attacks do have to make sense inRP (so no killing because of ooRP motivations only).
The reason for this change is that although rulewise a Core 1 base does not require RP, in practice both house governments and unlawful factions have forced the majority of those wanting to build a base to conduct RP with others. It would not be fair to have all that effort to build a POB and then have it destroyed without notice.
And yet still no change about the amount of time required after a noticed is posted, so all your doing is making it to where someone just has to make another post somewhere before they can burn a base, I don't think this rule will change anything about core 1 bases getting nuked