Spotting enemy aircraft (online)

[Redroach]

Recently, after flying many bomber missions, I've decided to try out the fighters, for some change. And after getting somewhat comfortable with the Hurricane and with the Spit Mk1a (both 100oct), I set out to get into combat on the ATAG server.
However, I find it quite hard to spot enemy aircraft; bombers in particular. Yesterday, I encountered several Me109s (and got pretty much outclassed by them ), but, I've yet to meet one or more bombers, be it AI- or human-piloted. I followed Vectors from Chain home, looked for AA explosions over the RAF's home territory, but nothing so far.

I don't want to cry "Bug!" on this, but did I do something wrong perhaps? Could it be the same issue as it is with the tree setting, where you have to change (and, optionally, re-change) the setting in order to have the trees displayed properly? Can I get some additional hints on where flak explosions are mostly positioned, in relation to the plane being shot at? Has someone had similar experiences? Or do I just have to look harder?
Reminder: I'm talking about online play now.

P.S.: I run a resolution of 1920 x 1080

P.P.S.: I remember actually getting visuals on AI bombers on the ATAG server quite some time ago... I believe it was in the timeframe of the second-to-last patch.