Frequencies conundrum
This has been bugging me for some time and I finally decided giving up in trying to find an explanation all by myself and am now requesting your educated opinions on how it happens.
Example:
We are flying through, say LFRR, assigned frequency 126.115.
The controller contacts another traffic in the same frequency and instructs:
"XX123, contact Brest, 132.210, same controller".
Next, we then hear the controller and XX123 establishing contact on 132.210, in spite of the fact that we're still on 126.115.
Anyone cares to explain how this can happen? How's what is going on in 132.210 ported to our frequency? Is it an ACC actionable option? If so, how?
Thanks for any input.