Was the date of 26th. a typo?
If not this is very confusing, according to Assoc. Dunkirk Little Ships Advance did not leave Teddington until the 28th., leaving Dover for Dunkirk on 29th. and returning (being beached at 05.30) I assume the next day 30th.
Just thought, do any of our members know if there are any records at The National Archive that might help, not something I know much about.