Parallax issues - Athlon Optics 10-40 x 56 mm Rifle Scope 30 mm Second Focal Plane (SFP)

Seems I'm having the same issues others are..

Parallax adjustment won't go out past about 350yds.

Got the scope back in Dec 2018. Noticed when I first took it to the range I had to dial out to about 125-133yds to get a clear sight picture at 100. Went to shoot a 600yd match today and couldn't get a clear enough image to even shoot turned all the way to infinity.. At 350 yards I could still pick off daises on the range though..

And dang, let me tell you it was a perfect day for a match.. No wind at all. Folks were laying down 20 round, 2" groups at 600 all morning long..

Just sent the above info to Athlon and will see how they respond. I've heard they're dang good about Cust Service. I've got about 4 other Athlon scopes that all perform flawlessly. Everything else about this scope does what it's supposed to do.. Hods zero very well, tracking is good on elevation and windage. Just a sucky parallax adjustment