On 23 June 1940 , I. '' Gruppe '' was moved to a forward airfield at Grandvilliers for in preparations for missions over the Channel Coast , but the following day , all Bf 109s were sent to Wiesbaden , via Brussels , for a thorough maintenance check .
On 23 June 1940 , I. '' Gruppe '' was moved to a forward airfield at Grandvilliers for in preparations for missions over the Channel Coast . 
 On 24 June , all Bf 109s were sent to Wiesbaden , via Brussels , for a thorough maintenance check .