Changing handicaps halfway through series

Simple question: possible not so simple answer.

Is there anyway of changing a handicap in Sailwave halfway through a series,
while keeping the original handicap for the earlier part of the series?

We review our handicaps on a six-month basis so it is possible that a
particular boat would be using one handicap for the first half of a series
and a second handicap for the rest of the series.

To-date I have calculated results and then used Sailwave but it would be
useful if Sailwave could do the whole thing.

Regards

Sam Kent