Ring them and ask. They were perfectly happy for me to break their seal on the cut-out (main fuse) in commercial premises in hertfordshire, and they never bothered to come and replace it. They didn't even bother to replace it when they came a few months later to uprate the fuse on another phase in the same cutout.
I have never been asked, but others have. I suspect it depends if the job looks like it has been done to professional standards.
I don't think the guys who deal with the cut-outs and meter tails will do it themselves. If they are concerned, they will ask for an inspection certificate.