the election can be revoked at any time prior to the expiration of the three year period beginning on the due date of the taxpayers' return not including extensions. file an amended return revising form 8949 for the year of sale and not take the 121 exclusion. however, for your current home to get the full exclusion after revoking the prior one it must have been owned by at least one of you for any 2 out of 5 years before sale and also have been occupied by both of you for 2 years out of 5 years before the sale as your principal residence. the information you provided does not make this clear. the dates of occupancy do not have to be the same.
