It appears that the organization id field on organization object, as returned by api call, for example
.../api/v2/organizations.json
has changed its value recently.
For example, for ArtsVision company, it used to have format 2*******8 but now it is 2*********7
(removed middle numbers for security reason).
Most likely, the change took place around 2019/05/02 (this is "updated at" value on api organization object. Could you please confirm this?