As we speak Phoenix is currently listed as being down on BGT website.
Thinking about this logically, I'm not sure why BGT would want to remove Phoenix and replace it with a ride like Wild Surge to open land up. Wild Surge is kind of a hidden ride, however, it's surrounded by very nice, large rock work which I'm sure BGT wouldn't want to remove. Plus with the amount of rides BGT has closed recently, I question why they would want to close yet another ride, especially a thrill ride like Phoenix. To my understanding though, Phoenix is a pretty old ride (actually over 30 years old, wow!), however, I'd rather see them replace it with another thrill ride as opposed to relocating another ride.
I just don't see why BGT would want to "close" Jungala, it's one of the nicest areas of the park and it's relatively new! (only added 10 years ago). If anything, the area by Gwazi is desperate for some work.