Rent increase notice allowable as part of effective new rent start date ?

Hi all wanted to run something past you to see if i've miscalculated the RTB calculator.

Tenant started on the 01/03/16 for 1100

This was prior to Dec 2016 so the 2 year rent increase cap applies.

I need to give 90 days notice so the notice will be on the 01/03/18 to take effect from the 01/06/18

When i put this into the RTB calculator it is suggesting that the 90 days notice that i am giving should also be included in the rent increase ?

R x (1 + 0.04 x t/m)

€1100 x ( 1 + 0.04 * 27/24) = €1149.50

as opposed to

€1100 x ( 1 + 0.04 * 24/24) = €1144.00

I understand some people will suggest that the rent increase is from 01/03/16 - 01/03/18 but the effective start of the new rent (as I am not allowed to give it 90 days before the 01/03/18) is really 01/06/18

Any thought or opinions welcome.