Unable to move promotion from Approved to Worksheet

Gretings,

We have a promotion on Approved status and we wish to revert it back into worksheet status, normal procedure, however when we summit the change to conflict check we get the following error:

startDateTime, Promotion component detail start date cannot be later than the promotion component end date

RPM log shows the following:

<message>

  No cause associated

</message>

<problem>[com.oracle.retail.rpm.promotions.vo.PromotionComponentDetailVo@39f6c7bf, startDateTime, Promotion component detail start date cannot be later than the promotion component end date.]</problem>

</com.retek.platform.rules.RuleException>

The weird part is that the promotion goes from the 13th to 28th of the current month, same as the details. The promotion as a whole is an oddball:  some items somehow where cancelled with start dates on 13th and end dates on the 7th, meaning the had to be active at some point. Some items are in a Canel Pending State with the same issue with the dates.