Sorry I can't remember the dates (probably late eighties or early nineties) but I attended twice when they were in a basement below a block of council flats in St John Street, Islington/Finsbury. Once when Mike and Penny Seeger came over and another time when Guy Carawan was there. On that evening the organizer in a slightly inebriated state complained loudly while he (Guy) was performing that Guy was singing the same songs that he been doing in the fifties. The same person that I had once to eject from the Ballads & Blues Club when he was in a similar condition.
If I can locate the photographs from the night with Mike and Penny I will have a date.