BADR s169sc & d elections.

[xinaxb]

As I understand it if you become diluted below 5% as a result of a fundraise (all other criteria being met) then you can make an election s169sc to effectively crystallise the gain and ensure receipt of the BADR (formerly ER). S169sd allows the deferral of the gain until such time as the shares are actually sold.
My question is : If CGT rates subsequently change is the tax payable on what was a notional transaction at the price of the funding round that effected the dilution and used to calculate the deferred CGT, revisited, or is it simply that, a deferral. What if you finish up eventually selling your shares at below the notional transaction price and the CGT rates at that time are higher, is the “loss” available to offset other gains at the then higher rate? ? I presume any gains on sale above the notional transaction are simply assesed to CGT at the then current rate.