And here we get a Cavern Club history lesson of straight from the early member's memory bank.
"The Catholic church was in charge of running it as a place for soldiers and sailors to go where they wouldn't meet bad women and get drunk."
Not an easy ask for any club, but to ensure the Cavern Club's young women didn't fall into the 'bad' category female members were closely vetted by their parish priests. Joyce passed muster but admits to not always sticking to the no-date rules.
"How could they stop us having secret meetings with the boys? Monsignor would come hunting for us on his bike but we were pretty hard to find".
We didn't learn all this at the Abba concert. Enthralled by Joyce's passing mention there of the Cavern Club, we set up a date of our own with her, we knew there'd be more to come - of course there was, lots more.
But before we follow the numerous tangents she takes us down we haven't quiet finished with her Cavern Club days; they extended into the Beatles' era, well before Brian Epstein talent-spotted them there.
When they first rocked Joyce off her feet Ringo had yet to be recruited, Pete Best was the drummer "and very good he was too", she critiques.
With Rotorua so far from Merseyside we can't wait to find out what brought her here.
Fate's the answer - Joyce is a firm believer in it, just as she is in ESP and the presence of spirits: "My granny was an Irishwoman".
Her original New Zealand destination had been Palmerston North, she'd formed an attachment to her long-time pen pal who lived there, he proposed, she accepted. " My mother approved, that was very important for a strictly brought up Catholic girl".
She set sail for Melbourne where it was to be "all change for Auckland". Joyce missed the boat. "I met this boy on board, he became my husband, I was 26 and very naive, I knew 'aught from naught', I'd never seen a man with his clothes off".
For two years Joyce was a clerk at Melbourne's Queen Victoria Hospital, that was until she was wheeled into the maternity ward to be delivered of twins, one of each gender.
They were two when their fitter and turner father was offered a job in Kaitaia. "We looked it up, it didn't seem very central, Rotorua did, so suddenly here we were".
That was 1962, Joyce's clerical skills were just what the Health Department needed, she was recruited on the spot.
Soon after their Rotorua arrival the then Mr and Mrs Birch built a house in Owhata; their marriage foundered there.
"Suddenly I was a woman on my own, not able to get a mortgage, I borrowed from the PSIS and bought a great bit of land in Holdens Bay but the house was ghastly, not even any hot water, so with only $3.50 a week maintenance for the twins I was really struggling to cope".
Joyce is a coper and cope she did, later remarrying. She met her second husband, Ron Rossiter, through their shared workplace, the then Government Building in Haupapa St. He was with the Maori Land Court, downstairs from the Health Department. "We clicked, the twins adored him."
Mention of Joyce's twins leaves us both moist eyed. Bone marrow cancer claimed daughter Linda's life.
"She was always fit and healthy, full of life, her son was a toddler and she and her husband were trying for a second baby when she was diagnosed, it was devastating."
When government departments were shipped out of Rotorua, Joyce was jobless. "I was too young to retire, I became an information recorder going door-to-door but it wasn't really me."
The museum was, Joyce answered a council ad for a clerk, jubilant when she discovered she was to be at the museum.
"It was the days when John Perry was the director, we did a lot of fascinating, quite wacky stuff. Tudor Towers [nightclub] was still upstairs, the first thing I had to do on Monday mornings was mop up the beer running down the walls and sweep up piles of broken glass . . . such an insult to that beautiful building."
The spirits Joyce "felt" in the basement were a museum bonus.
Plain-speaking Joyce says she lost Ron not when he died 18 months ago but when he developed dementia, no longer recognising her.
"It was very sad, don't ask if my faith sustained me, if there was a God would he let my daughter die, my husband lose his mind? No, I'm not convinced he exists."
JOYCE ROSSITER:
Born: Liverpool, 1933.
Education: Primary years Isle of Anglesey, Wales (where evacuated during the war), Notre Dame Grammar, Liverpool.
Family: Son and grandson.
Interests: Music "that's why I was at Abba", dancing "I can still dance, Ron and I did a lot of Latin American dancing", tennis in younger years, cards, "walking my friend's dog, I've a half interest in her."
On the Cavern Club: "I loved it, it was all go."
Personal Philosophy: "Live one day at a time."
