This was merely a clarification to fix some language in Bill C-24 which was not clear about this, arising from the way the transition provisions were composed in Bill C-24.
Prior to the transition provisions governing pre-June 11, 2015 applications taking effect, the Citizenship Act was clear, that pre-June 11, 2015 applicants had to continuously meet the requirements right up to taking the oath. Some grabbed onto ambiguity in the transition provisions to argue that the law left a gap in the application of the relevant provisions. This amendment simply corrects that to make no doubt.
As long as I have been following citizenship, going on a decade soon, the policy has consistently required applicants to meet all requirements at the time the application is made and continuing right up to the taking of the oath. Thus, for example, if the applicant spent so much time abroad while the application was pending that the applicant was in breach of the PR Residency Obligation, that would render the applicant inadmissible and not eligible to take the oath . . . and back when some applications were taking three plus years to process, this indeed did happen. There were cases in which applicants got the notice to take the oath, were abroad, and upon arrival at the PoE to come to take the oath their lengthy absence was noted or reported, and when they showed up for the oath instead of a citizenship certificate they were given RQ (some were reported for a breach of the PR RO and lost PR status . . . even though at the time they applied for citizenship, they were statutorily entitled to a grant of citizenship).
This has particular significance for PR-refugees who may have obtained a home country passport or traveled to their home country. Even if they fully met the citizenship requirements as of the day they applied, IRCC or CBSA could initiate cessation proceedings based on alleged reavailment, ending the individual's status as a protected person, which automatically terminates the person's PR status, and that in turn renders the individual no longer eligible for citizenship. Many (including me) think this is draconian, particularly when applied to persons who have a citizenship application in process -- under the Harper government, it appears there was deliberate screening of citizenship applicants for this . . . and more than a few such refugees had posed a question at this site about whether then needed a passport to apply for citizenship, were told they did, so they obtained a home country passport, and then CIC identified the applicant as a refugee who had obtained a home country passport and made a referral for cessation proceedings, so the individual would not only be denied citizenship but lose protected person status and lose PR status.
In any event, there was not even an arguable loophole for anyone who has applied since June 11, 2015.
To be clear what this is about, it means for example that a person arrested for drunk driving the night before the oath ceremony will not be eligible to take the oath. Or a person who is charged with domestic violence, even as of the morning of the day the oath is scheduled. It also means that even though a person submits paperwork showing he or she met the language ability requirement, IRCC can still deny citizenship if the person does not demonstrate such an ability at the time the person is called in for an interview. And so on.