Why would they register it any earlier if it's not required?
Why expend the legal fees to do it unless you think you'll use the acquisition vehicle?
To be fair you can do it yourself for £9.99 like. As long as you have sufficient ID.
Doesn't this support my point though? If they've used Pinsents for it (not cheap, they're big), that means they're likely to have asked for advice on what is required and for lawyers to run the process for them.