Page Rank update cannot be predicted beforehand. Google has its own algorithm for Page rank update, and we will come to know about it once Google has performed the update.
Google have its own algorithms.That depends upon google.. Also Using Google Webmaster tool.. For updating a page rank..
And We also some manual techniques like
Inbound linking
submission
article
blog
social media
there are various method to increase the Google Pagerank. i have already share how to increase Pagerank . there are off page method to increase pagerank:
Directory
Articles
Press Release
Social Bookmarking
Guest post
Foru