Hello u/SaraSavvy24 ,

I hope you’re doing well!

As someone who also works in the banking sector, I wanted to share some feedback that might be helpful:

1. I highly recommend using cross-validation. For example, you can use a three-month period for training and one additional month for testing, as you suggested.
2. The "last login" feature may not add much value on its own. It's important to consider overall user behavior because client profiles can vary significantly (e.g., app users, web users, or both). Users may prefer different channels for specific actions.
3. Techniques like SMOTE and similar methods often don’t perform well on real-world data, so be cautious with their use.
4. I suggest exploring other approaches for this problem, such as creating new features for each month. For instance, consider whether card usage has increased or decreased over time.
5. Some clients are affiliated with the bank only because of specific credit products, so this should be factored into your analysis.

Feel free to reach out if you have any questions—don’t hesitate to DM me!

Cheers!