Mail syncing when connected. [duplicate]

I'm not sure if I understand the question right, but maybe it's only half an answer:

I have my accounts set to be checked at a certain interval (30mins IIRC). Still, when I go offline (over night for example) and switch back to online, mails are not checked automatically as soon as Wifi connection is established. I'd have to wait for max 30min or check manually (which is what I do).

I agree this is notr an answer to my question!

for all sync options in "Setings > Accounts > email account"

"mails are not checked automatically as soon as Wifi connection is established"

If user is in always-on mode it will work(only exchange for now), for others does not make sense to surpass the defined sync intervals, otherwise other users will complain that defined sync times are not respected. Also is not a good idea to start all background processes once network becomes available will impact usability for sure.

I disagree with You ...because it was a request for an OPTION, additional to existing ones ...