Can't help feeling like most people are missing the point here.
This is nothing to do with reducing the number of immigrants - it's already established that, under the Rwanda deal, there will be almost exactly the same number of people coming into the country.
This is the beginning of the 2024 election campaign.
Think about it - the Tories set it up specifically so that it would fail a Supreme Court test, because the deal with Rwanda was codified in an unenforceable Memorandum of Understanding (against all precedent) instead of a treaty, and there's documented evidence that everybody involved knew it would fail. The Supreme Court ruling is based entirely on that failure, and didn't examine any further failures in detail on the grounds that it took precedent (it's not the court's job to give them a list of things to fix). So...they fix that by negotiating a treaty change - that'll be a couple of months, and then it'll get right up to the wire and a new court challenge will be raised, which will be another two or three months. That takes us up to March/April. It will almost certainly fail again on the grounds of human rights, and then Sunak will announce further changes and we go round again - so we're up to October/November.
The point is to make it look to the drooling masses like the Tories are battling against the system to do the absolute best for the country, and it'll dominate the headlines. In terms of election campaigning, that's a win.
And, if by some miracle, they actually win at any point in the game of whack-a-mole they've set up, then they can proclaim that they've done something for the country's best interests that nobody else has managed to (despite the fact that it will make no difference to the overall numbers, other than reducing the immigration backlog they artificially created with their incompetence).
Whichever way it goes, they can spin it to their favour.