I am working on a regression project. But I am facing the problem of covariate shift in features due to time delay.Test data was collected a year later due to which there has been some change in distribution. The research paper that I am working on also mentioned this shift in feature values but didn't mention anything about rectifying it. 

I found [this][1] but it talks about changing training set distribution.
What I need is a way to make test data distribution closer to training data or some other way in which I could control for it. A little note i am using `sklearn` and `Elastic-net` for regression.


  [1]: https://datascience.stackexchange.com/questions/28331/different-test-set-and-training-set-distribution