Regional flag size limits?

[Tinhampton]

When trying to upload a regional flag, you are prompted that "Your image may be resized and compressed" without further details. Unlike with banners and national flags, I don't know of any documentation vis-a-vis how large regional flags can be. However, I see that A Hole To Hide In has a 960x540 flag; 105 has an 800x600 flag; The Pacific has a flag of around 80kB.

So, if I may ask for confirmation of this point - exactly how large (in terms of width, height, and filesize) can a regional flag be? Also, are there any useful flag size loopholes we should know about (as there are with national flags)?

[Tinhampton]

It would still be nice to have some clarity on this point.

[Refuge Isle]

You can keep a region flag of up to 375 pixels wide and 250 pixels high. If one or another dimension is larger, it will be resized with the same aspect ratio you upload it with.

Similarly to nation flags, region flags possess special "oversized" exceptions, where you can have a theoretical maximum dimension of 1125 x 750 pixels, if it is under the 150kb cap, without being resized. If it is over 150kb, it will always be compressed to save space, and this can affect the picture quality.