Hot Desking and Forwarding

In our practice we have a large amount of users that move from building to building and then need to have other users phone calls forwarded to them. But if we forward calls to the user hot desk'ed into a different phone than their assigned desk phone the calls don't make it to them. What we do in the interim is forward the calls to the physical desk phones DID. This process is cumbersome b/c it requires IT's intervention every time. I feel as if this is a huge design flaw and needs to be redesigned. If a user signs into a hot desk phone their DID should override the DID of the phone, so users can forward calls to the user signed into the phone. If this isn't possible then what is the point of being able to sign into the phone to being with.