This is interesting - Facebook is rolling out a new option which enables Pages to publish updates targeted to their top Page fans specifically.
As you can see in the description, the option enables Pages to create posts exclusively for Top Fans, in order to 'thank them or share exclusive content'. Some users have had the option available to them for the last few months, so it may already be active on your Page.
Top Fans targeting could give you another way to facilitate more community engagement, and foster stronger connection. By working to reach your most passionate advocates, you could help to keep them more active on your Page, and expand your reach through increased activity and interaction.
Of course, you do need a number of Top Fans to make it useful. For eligible Pages, you first need to turn on your Top Fans badge by going to your Page Settings and selecting the 'Facebook Badges' section.
The badge is only available to Pages with more than 10k followers (more info here).
If you do have the Top Fans option, you can check out your list of Top Fans in the 'Community' tab on your Page to see how many, and who exactly, you'd be reaching.
The requirements are somewhat restrictive - but helpfully, Facebook has also, seemingly, lowered the barrier for entry for Top Fans of late, which could make more members of your community feel more connected and linked to your Page. Anything you can do to fuel that can only help build your brand, and boost engagement.
It's not a magic solution to solving your organic reach issues, but it's another option to consider in your posting and planning process.