Hello,
Unfortunately, we do not have any control over the manufacturers of the yarn discontinuing colors and we do have an email in to the designer about updating the designs color key to match what yarn colors are actually available. I am not sure if any changes will be made to the charts but we have sent an email asking them to be updated.
As for the substitutions, you could use Camel for the Beige, Cinnamon for the Rust and Fern for the Avocado. Hope this helps :) Thank you!
~Kristi @ EPC