If it's most recently released then uh, a long time. Probably 2013, as that year had both David Maxim Micic's Bilo III and The Ocean's Pelagial which are both definitely top 10 contenders.
If it's most recently discovered that'd be only two years ago when I started loving Lift Your Skinny Fists Like Antennas To Heaven.
Nice, those are some great albums. So, going by this formula, I'd say...
...most recently released:
Anathema Weather Systems
This came out in 2012, and although it took some months to click, it has been a favorite of mine ever since.
...most recent discovery: Nine Inch Nails The Fragile
According to RYM this is my most recent 5 star, back in 2016 (actually that might be In the Aeroplane Over the Sea but I've known it for far longer than the NIN one lol). Although there have been plenty of amazing records since then, I feel that year was the peak of my development in music tastes, when everything felt fresh and new to me. Kinda miss those days, when I'd rip through a new album almost every day and find some gems in most of them.
But the thing with "top 10 albums" for me is that those records tend to take a lot of time to sink in and truly stay with me past the honeymoon phase, which might even last for years. Those are the ones I can go back to and really feel them intensely, no matter how long it's been since the last time to hit play. I should prob revisit some of my ratings now, hmmnn...