Hi Adam,

I'm answering to this old post because we had the same issue on our ServiceNow instance and we couldn't find any answer.

we had the same issue with the subject length, that was occurring only in pre-production and production instances, not on our development environment.

We have found out that it is due to the modification to the field length of a rotated table carried between instances using update sets. In this case the modification is applied only to the "parent" table of a table rotation and not to the rotated tables (shards).

In our case, table sys_email had the subject field with length 350, while all sys_email0001...sys_email0099 had the previous value, 160.

To apply modifications to rotated tables in different environments, you need to either apply the modification manually on all environments (remember to exclude the update from the update set!) or to synchronize the shards of the rotated table using the dedicated UI action on the table rotation group form.