I checked the source code of the page you linked to and see that the image sources are from a CDN and that you appear to be using an image optimisation tool of some kind, and that would account for the unexpected behaviour of the image block not using the specified image size.
Hi Nigel.
Sorry for quite long delay with my answer.
I just found and add code to disable CDN:
Header set Cache-Control "no-cache, no-store, private, must-revalidate"
And it seems to be working now.
Thanks a lot to your advice! 🙂