I found this plane that dropped to about 200 ft before climbing back to 2000 feet… I don’t think it is an aborted landing because I saw this plane over my head around 1000 feet in the air in west Vancouver…
take a look:
flightaware.com/live/flight/ACA8 … R/tracklog
Putting in the lat long 49.18 -123.22 in Google Earth, it may be consistent with a missed approach or go around since it appears to be between the outer and middle marker?
Not sure how accurate the position is though since it’s about 1/2 mile right of runway 08 Right center line so the above is just that, a thought… 
1/2 mile and 200ft. pretty low
Appears to be real.