When do we need to update KSYCOCA_VERSION ?

[Albert Astals Cid]

One of the release team files says

When doing release, update:
 * kdelibs/kdecore/sycoca/ksycoca.cpp --> ksycoca version number

When does this need to happen?

For every release? For every .0 release? For every .0 release + for 
alpha/beta/rc?

Anyone knows?

Cheers,
  Albert