I don't have a solid answer except to say that I believe numbers-wise, virtual are more frequent.It seems like quite a few of us have been selected for oath ceremonies at the end of May. Are those most likely to be virtual ceremonies?
The only in-person oath ceremonies in the GTA seem to be at the Scarborough location these days and it looks like they're less frequent than those in KW and Ottawa.
If you want to see/guess, you can check the date of ceremony against the publicly-posted schedules:
https://secure.cic.gc.ca/CeremonyCeremonie/en/Home
They're only posted for about a week at a time - but as far as I can tell, the days of the week at a given location are consistent. So if your date falls on, say, the 30th and location scarborough, in-person is possible (ceremonies on fridays and mondays). If it's the 28th, I don't see any Toronto-area location that does Wednesdays in person - so probably virtual.
(I've no idea offhand if they do in-person and virtual on same day - don't see why they wouldn't but don't know).