Is it possible to delete a formation after the

[Wdll]

Is it possible to delete a formation/units CORE, after the end of the first battle in a PBEM campaign?
In a campaign I play with another guy I have bought some off map artillery that we agreed to not do (I forgot), and while it was ok to not use them for a single battle, I don't want to keep not using them for the rest of the war. Apart from upgrading them to another unit, which would be like buying a new unit, is it possible to either just remove them and get some of those points back, or at least just delete them? I tried through the Change button but it wouldn't let me.