I don't understand how the table can make maintaining easier. You need to support multiple values in every branch even if the only one value is used. I'm sure unused values will became outdated pretty fast.

"alpha" and "beta" stages are not related here. The test should be skipped at these stages (I recommend to use skipTest() or the skipUnless() decorator rather than just make test always success). Magic number can be changed multiple times at "alpha" and "beta" stages. Release manager needs to update the test only when forming the first release candidate. And his should not do anything if the magic number was not changed in this feature release.