From BEF Ships before, at an after Dunkirk by John de S Winser

Operations at Boulogne and Calais

Having reached the French coast near Abbeville, the leading German army units were completing an encircling movement and, by advancing towards Boulogne, Calais and Dunkirk, were poised to sever any seaborne escape route. On May 21, MTB 25 was despatched to Cherbourg to collect a supply of French maps; the hospital carriers ST ANDREW and ST JULIEN transported military patients from Boulogne to Southampton. And the destroyers KEITH, WILD SWAN and VENOMOUS between them brought into Folkestone 468 civilians from Dunkirk, Boulogne and Calais respectively (sic). Two yachts, GREY MIST and GULZAR crossed the Channel to act as wireless links, the former at Boulogne and the latter at Calais, and in the evening the destroyer WHITSHED went alongside Admiralty Pier at Dover to embark anti=tank guns for what could prove to be an opposed landing at Boulogne. She left at 0520 on May 22 in company with the destroyer VIMIERA and the passenger ships BIARRITZ and QUEEN OF THE CHANNEL carrying part of a Guards’ brigade. They were followed at 0948 by another passenger steamer, MONA’S QUEEN, with the remaining troops. The initial arrivals found Boulogne still in French hands and, with the aid of the Thames tug GONDIA, the ships were able to berth alongside a quay described as being in complete chaos.

There follows a section about POWs and civilian evacuees, then May 23:

WHITSHED and VIMIERA entered and berthed alongside, to witness their ships being rushed by panicky British soldiers of the Pioneer Corps who had to be controlled at bayonet point. In contrast the well disciplined Guardsmen boarded WHITSHED ….. both ships left for Dover at 2025.