Oakland has clearly said
No idea what standstill is about?
<sigh>
I think the question mark at the end of that sentence makes it clear that it was a rhetorical question, not a statement.
I also don't know what more can be done to clarify the legal position around keeping a single pig, since Oaklands has provided what looks to me like a very comprehensive and detailed breakdown of the relevant legislation.
To summarise: there is no direct statement in law that it's illegal to keep a single pig; there are clauses in legislation that imply that pigs should not be kept alone; if you're intending to keep a single pig please take the time to check with the relevant authorities.
From a welfare perspective I don't believe it's healthy to keep a single pig, but that's not the law, just my opinion.

So please, can we move on? (In case of doubt, that was another rhetorical question.)
Thanks,
Dan