Sudden change in my family's election status on Williams County wells

Hello all, I haven’t posted for awhile but now I am in a quandry. My family and I have approximately 16 wells in Williams County just north of Williston, since 2012-2014. Our first well was participation; all the others we signed an election letter not to participate. 2 months ago we received a notice that they wanted us to lease last three wells that just got re-started [they were lying dormant the past 4 years]. Oasis listed them out and we opted to lease these three at 20% for three years. However, we had elected not to participate in these wells when initially sent out our election papers in 2014. Anyway, we received upfront bonus money for leasing these three wells.

Then 2-3 weeks ago my two siblings got a standard letter with a request to re-sign division papers on those three wells since the status had changed. I still have not gotten my letter yet and evidently will get it in August. This letter listed our 7 other wells that had Harbour in the legal description, for example, Harbour 5501 13-4H [T155N-R101W-lot 24]. Neither one of my siblings questioned this, signed these seven division orders and sent them off.

My question [our landman also has these questions but has not gotten back to me yet] is: can an oil company change an election from non-participation to a lease situation without our prior knowledge? Since there are only 3 elections, participation, non-participation, and leasing, I thought the original election we chose remained the same. We have the above-described well almost at full payout to the oil company; we now get 16% on that well, and once they have zero left to collect on their investment, we should then receive the full 100% of our mineral interest.

Can both of these elections exist on any particular well? Any help with this would be greatly appreciated. Pat Maloney