seems to me i saw something about this the first time the updated app appeared on my phone, but i can't find it now, i would like to turn off email preloading not just in my phone, but in the browser on my laptop. it is kind of annoying to have to look at emails that i am selecting to be deleted and it is really annoying when i'm somewhere with low bandwidth.
I don't know what app you're using on a phone, but on the laptop, instead of selecting the message by tapping it, just check the box to the left of it. That will select it without opening it, and you can then just delete it. Or as many as you like.
In the Comcast email browser app there is a black bar running across the top of the screen. Click it on the right side (to the right of the '?'. This will bring you to the "Mail Settings" page. The second option under "Display" is "Allow pre-loading of externally linked images." Is that what you're looking for?