John, Mike, Khronos, Rob, Wolf, Badersk and DixieGal -- thank you all very much for your help. Slowly I'm getting there!
Deleting and re-establishing the wifi connection and switching off the iPad (rather than letting it fall asleep), seemed to have reduced the problem. Failures to automatically reconnect occur less frequently, and when they occur I no longer need a dozen or more manual attempts before the connection is re-established.
That in itself eliminates at least 80% of the nuisance.
I also got the advice not to put the brightness of the display to a minimum. (Which I often do, no idea how that can be related to wifi connectivity...) Since I put the britness one notch above the minimum, I have not had a single disconnect.
DixieGal, is the update you mention installed automatically? (no, I'm unlikely a better techie than you
)
Thanks again all.