Sorry, I'm not sure how to search this topic.

I've redeemed E-rewards at $50 for 3000 Hilton points. I last did it last May; now, after regularly answering surveys and being kicked out of most, I've reached $50 again, and see that it's 2500 points now, but I could build up to $75 for 4500.

In deciding what to do:

What are the current rules for expiration of E-rewards?

Do you think I have much risk of the program being further devalued before I reach $75, or of being shut down completely?