Nares breakup, my favorite subject...
In statistical reality this is a vote between June and July (the poll has a too-low resolution). Given that the definition demands breakup far above the arch, I voted July, also considering that the arch is is a stable location and that it's been a cold year in Nares.
A possible surprise would be for this to happen in the second half of July. Of course, early breakup (first half of June, May) is also possible, but IMHO improbable. Northern arches have more volatile dates.