Say a circle is rotating about its centre at a relativistic speed.  If it were not rotating in your reference frame, its circumference divided by its diameter would be $\pi$.    Now, because it is rotating, let us say we have been using little sticks all along to measure circumference and diameter.  We would need a ratio of $\pi:1$ sticks to build the static circle.  However, these sticks change when the circle is spinning because of length contraction.   So, the sticks along the diameter become thicker, but not shorter.  The sticks along the circumference, however, become smaller, and not thicker.  Therefore, if a circle is rotating in a reference frame, $\frac{circumference}{diameter}$ is not $\pi$.  This is an example of relativistic geometry.  My question is: how does area change?  I believe the area becomes larger.  Here is my reasoning:  The rotating circle has a larger circumference than before, therefore the 'new $\pi$' is greater than the 'old $\pi$'.  And, because this circle is spinning around its centre, it is still a circle to you even when its spinning.  Therefore, area is still $\pi r^2$; but this time, $\pi$ is larger, therefore the new area is larger.  I can also think of a counterexample:  Imagine using a bunch of smaller circles within the larger circle to estimate its area.  When the circle begins spinning, these circles shrink because of length contraction.  Therefore, these circles become smaller, and the overall area is smaller.  However, this may also be interpreted as changing the metric of the space by requiring more sticks to create the diameter of the circles, contradicting the argument that the circle gets smaller and actually agreeing that it gets larger.  Which is correct?  Why?  EDIT: I chose to distinguish my question from others because the reasoning I offer is not something explored in-depth in other questions/answers and is a part of the question that I believe enhances it.
Let us say you are in an inertial reference frame with a circular planar disk. If you take your meter measuring rods (or perhaps tape measure) you can find the diameter and circumference of the disk. If you divide the circumference by the diameter, you will get exactly $\pi$. Now you start rotating the disk. A book I have claims that now the ratio will be different (lets call it $\pi_\circ$ to avoid ambiguity.) This has caused to reevaluate my understanding of special relativity (this is a set up to general relativity, but the problem itself only requires the special theory.) My problem is that, sure, the measuring rods (or tape) would contract on the circumference, but wouldn't the circumference contract a similar amount, therefore giving a measurement of $\pi$ in every reference frame according to your own measuring rods. Of course, this reasoning goes on to make me question how I understood all of special relativity up this point.
I understand that the first point release of Ubuntu 18.04, namely 18.04.1 is now available and that my system should now offer it as an update.  My current OS version is 16.04.5 LTS. In System Settings/Software and Updates I have set 'Notify me of a new Ubuntu version' to 'For long term support versions'. I have tried both the main server and the server for United Kingdom, neither offers an update when Software Updater is clicked or via the Ubuntu Software icon.  Can anyone please tell me why I don't get the option of updating to 18.04?  Edit:  I don't remember the details exactly, but I think that my last LTS point release update was offered automatically a lot sooner after the published release date than where we are now with 18.04.1.  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