I just found out that Wyeast has discontinued several yeast strains, including my all-time favorite 1026 British Cask Ale.

Here's the poop on substituting the discontinued strains with strains that are still available:
Hi Chris,
Thank you for your assistance with this! I hope you will help us get this information out onto the discussion boards and forums, as you've suggested.
Here is a listing of discontinued strains and our recommendations for substitution:
Discontinued --> Substitution
2002 Gambrinus --> 2000 Budvar
2247 European Lager --> 2042 Danish
2272 North American Lager --> 2035 American Lager
3763 Roeselare (on the current VSS list) --> 3278 Lambic
1026 British Cask Ale --> 1968 London ESB
3538 Leuven Pale Ale --> 3787 Trappist High Gravity
1882 Thames Valley II --> 1968 London ESB
3864 Canadian/Belgian Style (nearly certain to be on the next VSS list) --> 3787 Trappist High Gravity
3725 Biere de Garde (on the current VSS list) --> 3522 Ardennes
3726 Farmhouse Ale --> 3724 Saison
1768 English Special Bitter --> 1968 London ESB
3822 Dutch Castle --> 3463 Forbidden Fruit/3522 Ardennes
Thanks again for your business and support.
Jon B. Graber
Marketing and Sales Manager
Wyeast Laboratories
888.349.2004