Nah, this post is a bunch of nonsense. From the plans that were fascinatingly leaked 2 months ago:

The prime minister and the queen have agreed that the day of the state funeral will be a “Day of National Mourning.” This has also led to planning issues. The day will effectively be a bank holiday, although it will not be named as such. If the funeral falls on the weekend or an existing bank holiday, an extra bank holiday will not be granted. If the funeral falls on a weekday, the government does not plan to order employers to give employees the day off — the documents say that is a matter between employees and their staff.

I’ve got no idea where they got the 12 day figure from, the plans just describe the events in the 10 days between death announcement and funeral.

Honestly, I wonder if she is actually dead or close to it, they’re holding off on announcing it to avoid an unparalleled super spreader event due to her funeral:

The Department for Transport has raised concerns that the number of people who may want to travel to London could cause major problems for the transport network, and lead to overcrowding in the capital.

In a striking assessment of the scenes that could unfold, one memo warns of a worst-case scenario in which London literally becomes “full” for the first time ever as potentially hundreds of thousands of people try to make their way there — with accommodation, roads, public transport, food, policing, healthcare and basic services stretched to breaking point. Concerns have also been raised about a shortage of stewards for crowd control purposes.