Teachers don’t tend to advise last-minute cramming ahead of big tests.
For the government, tests don’t come much bigger than the return of millions of pupils to classrooms in England next week.
And for schools, this new guidance couldn’t have been much more last minute.
One union leader said there was a “weary inevitability” about this latest information – coming as it did late on a Friday night, days before term starts and ahead of a Bank Holiday weekend.
Officials say the new guidance doesn’t require schools to make any further changes ahead of next week’s reopening.
The government is also emphasising that these are “last resort” measures and that the majority of information for schools was published in July before the summer break.
It is true that a lot of the four-tier system is a formalisation of existing guidelines.
What is totally new though – and what will be adding to the stresses of teachers – is the possibility of running a “rota” in the event of tighter local lockdowns.
This would involve splitting the school in two and keeping one half at home learning remotely for two weeks while the other continues to come in.
That will require a change of contingency plans that many head teachers may have already submitted to their governors for approval.
But perhaps the bigger impact is on trust between teachers and ministers.
The exam results fiasco left many school leaders frustrated and angry with government.
The timing of this announcement will only add to that, even if much of the substance is not a surprise.
None of this should impact on schools reopening next week though.
On that, the government is feeling confident.
Polls last week indicated that most if not all schools will be open with a vast majority of parents sending their children in.
But getting classrooms open again is only half the battle.
The government also needs to keep them open.
To do that, ministers have handed themselves a large degree of flexibility.
There are no set trigger for when schools will be moved through the four-tier ladder of restrictions.
No concrete rules either on when a whole bubble of pupils is required to isolate over a smaller group.
Like everything with coronavirus, that fluidity is partly down to the unprecedented times we’re living in.
But that doesn’t make it any less nerve-wracking for parents and teachers who are trying to plan for a plethora of outcomes.
It’s been a tough summer for the government, but winter may be worse.
All the while, public trust appears to be something it’s finding harder and harder to hang onto.