As for the first attestation you mention, Tacitus (d. early second century) mentioned the Anglii in a list as allied with the Eudoses (sp?) who were the Jutes... so like Ben, I don't really know what your point is regarding Alfred, and the difference between uses of Anglii and Anglisc.
Did not say the Anglii as a people were first attested at that time. Said the word "anglisc" was first attested at that time. Attested to meam first proven written record of the word's use.