Regarding migration to GST, part data on provisional IDs of Central Excise registrants has been received from GSTN and made available through ACES website. The remaining provisional IDs of Central Excise registrants and the Service Tax registrants are still awaited from GSTN and would be made available shortly.
As per discussion with Service tax helpdesk, they will start sending provisional ID for GST migration from 22 Jan 2017.