I was watching Carry On Loving yesterday (not one of the best but has its moments) and noticed the relationship between the characters played by Kenneth Williams and Patsy Rowlands. Kenneth always played these pompous, patrician types while Patsy would often be cast as a spinster-type secretary/assistant of some kind, usually quite subservient - a little dowdy and not really flaunting their femininity. I believe they were in four Carry On's together where this was consistent.
This was a kind of archetype you'd see in a number of comedies of the 1970s and I've a feeling that Lynn may have been based on those kinds of characters, with Alan being the pompous authority figure. She still retains that personality but as we know. she's become more assertive - sometimes crossing the line into "aggressive". (!)