Yes, I can answer those questions.
Presumably Clinton voters would have to wait too; however, since the primary is held on a Tuesday, Sanders supporters — since they are younger — would not be able to vote until later in the day, because of school, work, and so forth. Clinton’s base is elderly voters, so they can vote by absentee more frequently, vote earlier in the day when the lines are much shorter, and generally have more time to vote.
This is a problem because the majority of polling places were cut: http://www.azcentral.com/story/news/politics/elections/2016/03/22/live-arizona-primary-coverage-presidential-preference-election/82096726/
This would affect Bernie Sanders significantly more than Hillary Clinton, because voters arriving late could get discouraged by the long lines and the primary already having been called for Clinton with 1% of the vote in.
It is remarkably easy to only target Bernie Sanders supporters on the rolls, as one of the commenters noted in the thread I cited. You would only have to search for Independents who had recently changed their affiliation to Democratic (since 80%+ of Independents vote for Sanders) or Democratic voters under 45 or 30, because the majority of younger voters vote for Sanders as well.
As for not hearing of any Clinton supporters being switched, I’ve researched for months, poring over every comment of the threads I cited (and many more), news articles, forums, audits and lawsuit reports, and so forth, and I have yet to hear of a Clinton supporter being switched. It still most likely happened, but the message being conveyed is that the voter suppression overwhelmingly affected Bernie Sanders. I can edit the article to clear up any problems, but I hope I answered your questions satisfactorily.