L2100 Trial

We are going to activate L21 (10Mhz) 2 frequencies from U21 band.
At first, we wanted to do trial, My question is that. As Frequency would be used in L21 Dl from U21 Dl. So There should not be any interference for border area like L21-U21 Border cells for L21.

What can be the possibility for having interference in this scenario.

There will be, but not that much, you need to define an area where you will not use neither L2100, nor U2100, for your trial, we did it in our NW, we locked multiple cells in U2100 based on Drive test and from SOHO behavior.