Good question, Jean - I haven't noticed that at Surrey (though I also have not been in on the cams as much as you and the other Delta zoomers are) - and I'll ask Ken. I'd also suggest having those affected do a speed test (https://fast.com/ is one that's out there, and if you're a zoomer click the "more info" link to check your upload speed, which is how fast your instructions get to the cam) - it's possible that with the demands on the grid from the current high temperatures across North America, something other than us has slowed down.
Added - I just tried logging into three cams - Delta East took over a minute; White Rock CU and Surrey North took about 6 seconds each. I closed out of each cam immediately, and hope I didn't disrupt what the zoomers were doing - but it does show that there seems to be an issue at Delta.