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Under clause 8 on page 4 he is required to get consent for this alteration.
The requirement is not qualified so the freeholder could just withhold consent even if that unreasonable.
4.1 on page 5 has the usual provision about not causing nuisance.
The freeholder or management company if there is one require him to ask for consent and could put condition in that the lease is very to covenant which you have drafted and if he won’t agree to sell you lease in respect of that, then he doesn’t get consent and you can require property how it was.
Can I clarify anything?