Ideally the growing medium (compost?) should never dry out.
It's generally better if you can water from the bottom (by standing the pots in a tray or saucers and filling those) and feed from the top. The problem with watering from the top is it's hard to be sure that the water is penetrating to the root tips. A drip-fed irrigation system is probably best, but we've never gone to the expense ourselves.
Also we've never had blossom end rot with cherry tomatoes, only with larger varieties. Not much help for this year, but something to consider for next year?
Definitely don't cut down the foliage, if it is blossom end rot it won't help.