After taking a second look at the PHB Ranger and the UA Ranger, it seems that they both gain subclass abilities at 3rd, 7th, 11th, and 15th level, with the only discrepancy in the way the two versions handle their subclasses being at 5th.
So the easiest way to handle making a Ranger subclass that works with either the PHB version or the UA version is to design it with features for 3rd, 7th, 11th, and 15th level, then include a sidebar that explains that this particular conclave grants Extra Attack at 5th level if you're using the UA variant.
I'm pretty sure the only reason Extra Attack is tied to subclass instead of being a base Ranger feature for the UA Ranger was so they could give the Beastmaster Coordinated Attack instead.
Look-- as far as the Ranger class goes, they done well screwed up. Not the only thing in the game they have utterly screwed up by far.
But at the same time, they have too big of an ego and regularly pleasure themselves to their own superiority above all other imagined game designers to ever actually admit that they screwed up.
Hell, it is one thing in Magic the Gathering to say "this card was broken, we didn't really think through the consequences and so now a year or two later we deem it illegal and replace it with this similar card" which tends to happen for overpowered cards, but rarely for under-performing ones anyway.
But, apparently in D&D it is utterly unthinkable to admit mistakes and release a revise edition of something within the next 10 years of having released something.
So you are stuck, in a less polite term--- f*cked-- until they decide to release a 6th edition of D&D-- at which point they will feel free enough to undo mistakes done in this edition.
Because no matter what BS they fool around with in UA articles, they just don't have the intestinal fortitude to admit that they done screwed up and need to redo something and release a whole new version of the element of the game they flaked out on.
Which can only make me say "screw you M.M. and the rest of the totally incompetent doofs you have working on this game, because I am damn sure I could do a better job than you lot and that's not something I have ever said approaching any other games."
For D&D we are somehow stuck with the most utterlydesign team that could be assembled with all of their heads too far shoved up their rear ends to ever revise any mistake.
So, screw it-- you may as well redesign the Ranger from the ground up for your game because no solution is ever going to come from the official company.
*snip rant*
I would be really surprised if the ranger shows up in the weekly UA's. If the goal was to put things out in time for feedback for the big book of crunch, then mission accomplished with the last UA ranger article. Even if the feedback was terrible negative, it would still take a while to redo the ranger again.
From https://twitter.com/mikemearls/status/805278514463158273
[MENTION=22090]as[/MENTION]tiboga when we do ranger stuff, will work for both. Subclass nodes match up for both versions. #wotcstaff

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.