Command blocks on always activate do not activate after changing mode to repeat

This is mentioned briefly in MC-134603, however, they do not seem to understand what's happening.

To recreate:

1. get a command block (impulse or chain) on always activate.
2. place it
3. put in a simple command like /say hi
4. change the mode to repeat
5. observe as it will not say anything until you go to needs redstone and back