Rollover and payoff

Hi.

We rolled over a loan and created a new contract fixed period but now the customer wants to pay up the loan in the previous period.

Previous period: 2012-01-01 - 2013-04-30

New period: 2013-05-01 - 2014-04-30

Full Payoff date: 2013-04-18.

Any way to delete new new fixed period and revert to the old one with standard functions?

Thanks, Einar.