221111 is now entering service with XC today. It's currently allocated 1H14 Birmingham NS - Man Picc.
This means all 12 221's ex Avanti (221107-221118) have now entered service with XC.
The 221 fleet now and for the foreseeable future is allocated as follows...
221101 - 221106 - Spare + Unknown Future (Possible Open Access)
221107 - 221141 - XC
221142 + 221143 - Grand Central (Then Spare + Unknown Future + Possible Open Access)
221144 - XC
Also
@voyagerdude220 no, I don't believe 221107 has been in service since.