I assumed that he arrived in August, close to the beginning of the semester, but someone recently posted he had arrived in June (not sure what the source is, though, and this is definitely not confirmed).
Something interesting, though: the PCA is mentions his phone service plan began in June 2022 -- it's plausible he got a new phone / his own plan in WA once he moved there? In any case, I found it strange that his phone service plan started so recently -- that's something people don't change too frequently, at least in my experience.
EDIT TO CLARIFY: I looked at the PCA again and the exact date is June 23, 2022, but the account was linked to his address in PA, not WA, so it does not necessarily mean he was in WA as early as June. I do still find it unusual that the account was new, but it's possible he wanted his own account (and off his parent's) before he moved across the country.