With the current Journey and the Premium version which gives you the first 25 levels for the price, do you only get the first 25 levels or can you play the Premium version of the entire Journey, even the levels past Level 100?
Buying the Premium pass will give you access to the premium journey quests.
Buying the extra 25lvl premium pass will make your progress faster, buying the premium 25lvl pass will not auto-complete the F2P and premium journey quests, it will just give you the cosmetics and the RP of each lvl up to lvl 25...
...so you get to keep and do the F2P and premium journey quests to earn even more rewards !
To fully claim all the rewards this journey offers check your contracts page---> switch to "all" and type in the search bar "Alzur", this will show you what you need to do to get all the cosmetics.
Also like
@SphinxRage mentioned (corrected me) bellow you gotta scroll down the contracts page to find the remaining journey contracts.
Also check the Leader Skin selection screen for more tips on how to unlock even more cosmetics by using specific cosmetics while you play.
...and yes you do get to play beyond lvl100 for even more rewards.
Cheers