IHS more than expected for FLR (M) Renewal

Hello,

I am working on gathering all of the necessary information so I can submit my application to renew my marriage visa by Feb 2021.  I arrived in the UK in May 2018  with my first FLR (M) visa and on my BRP card, it says it expires Feb 15, 2021 so I am planning to submit my application within the next week or two.   so I get it before my current visa expires (hopefully)

I made it to the payment section of the online application and when guided to the  IHS payment page it  says that I owe £1560.00 for the IHS.  This is a lot more than I was anticipating.  Considering it says that the IHS is £400/ year.  Using that information I anticipated he IHS being  about £850 for a 2.5 year visa.

I cannot continue on to the next part of the application without paying and I'd rather not pay this fee without being 100% certain that I'm paying the correct amount.  Can anyone help me by explaining why I am seeing this total for the IHS?

Thank you for taking the time to help me. 

The IHS surcharge increased to £624 per year on October 27th 2020.

So, unfortunately, £1,560 is correct.

Having said that, even if it was still £400 per year, it would have been £1,000 for the IHS surcharge, not £850.

Old fee prior to 27th October 2020:
£400 x 2.5 years = £1,000

New fee from 27th October 2020:
£624 x 2.5 years = £1,560

From the IHS Surcharge webpages:

How much you have to pay

You’ll have to pay:

£470 per year for a student or Tier 5 (Youth Mobility Scheme) visa, for example £940 for a 2-year visa
£470 per year for visa and immigration applicants who are under the age of 18 at time of application
£624 per year for all other visa and immigration applications, for example £3,120 for a 5-year visa

https://www.gov.uk/healthcare-immigration-application/how-much-pay

And from the IHS fee calculation page for an FLR(M) visa:

Calculate your immigration health surcharge

Based on the information provided we have calculated that your total Immigration Health Surcharge is:
£1560.00