At Manchester, we now have "SAMOS" Semi Automatic Met Obs System. Before that we had Met Observer, [from the Met Office]. We now have Samos qualified ATSAs doing the wx obs.
"IF" the wx changes, on either system [aka "wx special"] then it is up to the "Air ATSA" to update the D/ATIS or not.
The ONLY time there is an "automatic" update is a QNH change
we aim to please, it keeps the cleaners happy