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This is one of those errors that has to do with natural language evolution. "Standard" is what's commonly used, not a blessed committee somewhere.
Ongoingly is certainly the correct usage of the term, when one wishes to convey a prospective continuation of a defined task - just for example...
Although I object to this term's common omission, with insistence toward its necessity, I relent that in some cases, it could be substituted by the term "thereafter", with the mere (perhaps insufficient) 'implication' that the discussed event or action would continue to occur.