Same results on XA2 Ultra on 4.4. Cost me 80% of my monthly data before I figured it out. A simple toggle of airplane mode solves it, but finding that was a little too late.
A more detailed analysis covering this issue can be found here: Android Connectivity Issues Analysis
Personally, on Xperia 10 iii I do have that exact same issue even in some native sailfish apps. For instance, the weather auto update from the event view doesn’t work in such situation. And my email are not gotten as expected, meaning always up to date (but searching manually for new emails work)
That’s why, for now, I’m keeping wifi off full time
I’m not sure native applications are impacted by the same bug (I may be wrong) as the weather “widget” is able to connect again once the user forced it.
Which email provider are you using? If it’s gmail, there is a bug relating the auto sync doesn’t work.
I’m using gmail and an exchange account.
Do you encounter the same problem with your exchange account?
Yes, same problem occurs for the 2 accounts.
Edit : I’ve done a trial here. I’ve switched from mobile data connection to WLAN. Then, I can still use the native sailfish browser, but not Aurora Store for instance. My exchange account was not able to sync either.
Disabling WLAN, I had to switch mobile data OFF then ON to make the connection to be fully stable and then, so that Aurora store and my email work again !