Furthermore, it could support a smooth relocation process by taking pressure off both supervisors and banks, for example by making "first mover advantages" less important. This being said, transition periods would be a politically sensitive topic in the negotiations, and it is unclear how likely such an agreement might be.
As mentioned earlier, we should not forget about the access of European banks to the UK, which is also an important issue. For German banks, for example, the UK is the second-most important foreign market, right after the US. It will be up to the UK Prudential Regulation Authority to decide under what circumstances European banks can retain access to the UK.