There are two elements to the notification that you need to keep in mind.
First is M&A law and limitations on acquiring companies making business decisions on behalf of the acquired company before the merger / buyout closes. This is very strict in most jurisdictions which is why when Hock was running his shadow Op of the IOC controlling VMware commercial policies (btw - some would call it more than borderline "improper" and expect that all the VMW execs knew it but just played ostrich ...). This is the first part of why notifications will be later for some jurisdictions than others as some have waiver conditions once regulatory approvals are secured and others don't.
Second is labour law. Many jurisdictions have a deeper public inquiry to large scale layoffs and there are reporting, review, approval schemes with government agencies before employees can be notified individually - see Germany, France, Nordics, etc... Others like the US, India, etc. have more lax rules here that can be addressed in a shorter timeframe.
In most if not all cases, there isn't a very easy way to string this out so you're looking at things being done and dusted likely within 90 days of the merger across all jurisdictions if Hock wants to go fast which after all this time I would assume he would intend.
It's happening and it's a question of weeks now.