Ground Rent Increase Query

betsybleu

My Ground Rent has recently increased by 100% (every 25 years). My lease was signed in March, 2000 therefore I was of the understanding the increase is not due until March 2025. However in the section 'the Term' of the lease it states ' Nine hundred and Ninety Nine years from 25th December 1997. Thus the 25 year period is taken from this date not the date I signed the lease in 2000 yet I had no interest in the property at that time. 
Can someone explain why the freeholders would put this earlier date when the property hadn't yet been purchased. The managing agents were unhelpful in putting forward an explanation.
Is it based on the date they may have acquired the building? 
Thanks

user1977

Was it a newbuild when you bought? Pretty common for e.g. every property in the same development to have the same notional start date. That ought to have been pointed out to you when you bought, but there's nothing "wrong" about it.

loubel

As user1877 says, this is common and nothing odd or worrying. Whatever reason was behind the start date is irrelevant as it is what it is and you knew it when you purchased.

DullGreyGuy

The date is the date... same if you buy a leasehold property of someone else you get what's left of the X year lease and ground rent will escalate in line with the start date of the original lease not from when you purchased it

betsybleu

Thanks all for your comments. It was a disused warehouse with units sold off plan for individual refurbishment.
I probably did know 23 years ago but having not read the lease in as many years easily forgotten. Its quite possible it was the year the building was bought by the freeholders/developers but as said earlier ' it is what it is ' and is due.