Two more from this morning.
As you can see Platform three is going to remain it’s current length. There is little they can do to lengthen it.
If you look at the OPs photos of platform 3, the section blocked by the embankment is actually relatively short. I’m not saying it would be extremely cheap to do, but it should be easily possible to cut back the embankment. Once you’ve done this there are no other real constraints beyond (other than the usual trackside paraphernalia) to extending the platform.

