Patch 1.19 will see further revisions to the guildleve system.

These revisions are intended to create a more flexible play style for levequests as well as streamline the overall system. To accomplish this goal, the ability to accrue and store guildleves will be introduced, certain aspects of regional and local leves will be standardized, and the guildleve system will receive an overall UI adjustment.

Guildleve Issuance

Guildleve issuance will be revised as follows:

Players will receive an allowance of four leves every 12 hours (Earth time), up to maximum of 99.
The allowance will be shared amongst regional, local, and faction leves.
The Adventurers’ Guild will update its list of leves when you complete (or fail) a levequest, or when an additional allowance is issued.
The ability to exchange leves and the associated bonuses will be abolished. However, alternate bonuses will be introduced by way of a new evaluation system.
* Players who have reached the allowance cap may choose to return leves.

Levequest History and Evaluation

Upon completing a levequest and collecting the rewards, the leve will be moved from the player’s Journal to Levequest History, which displays the details of the eight most recently completed leves. Requesting an evaluation at the Adventurers’ Guild with at least one levequest in the history will earn you a new leve, the nature of which varies based on your levequest history. At this point in time your history will be cleared.
* Leves issued via the evaluation count towards the player’s allowance.

In patch 1.19, the combination of levequests in the history will determine the bonuses granted upon completing a levequest issued via evaluation. However, the evaluation system will be expanded in the future.

Retrying Levequests

Players will be given the option to retry a failed levequest at the cost of a leve allowance.
Regional and Faction Levequests
The retry option will be available in the Journal entry, at the Adventurers’ Guild, and the aetheryte menu.
Local Levequests
The retry option will be available in the Journal entry, at the Adventurers’ Guild, and in the option menu displayed upon failure.

Abandoning Levequests

The option to abandon levequests will be added to the Journal entry. Players may choose to abandon leves regardless of success and failure.

Source: Lodestone Forum