Since I switched to Delta for almost every flight last summer, I've been incredibly surprised with how often they upgrade me. I made Silver last year since I switched late summer. I honestly didn't expect as many upgrades as I've been getting. Thrilled with it, but trying to understand how/why so I can learn this mileage program I've never really used before. I've hit Silver again this year already, and am going to reach Gold by the end of April.

I book economy exclusively. Usually full fare/unrestricted (gov YCA fares and once or twice a month a direct SFO-JFK at non-refundable economy market prices), but still always economy.

Excluding upgrades I know happened because Delta felt bad for messing up a flight, on average, I'm getting upgraded from E to F about 20% of my flights, and from E to C+ about another 30% of my flights. At Silver, that's a heck of a lot more than I expected.

Almost every single flight I've been on has been totally sold out. 90% of my flights are SJC-MSP-DCA, returning DCA-ATL-SJC. The rest are all SFO-JFK-SFO. Busy flights. Packed full.

But here's the real kicker. Two days ago (Friday), I left on my usual SJC-MSP-DCA. I'm sitting here at the gate in ATL waiting to board for my last leg home. On the trip out, I was upgraded to F the entire way, from SJC to MSP, and MSP to DCA. For the return, I was upgraded to F for DCA to ATL, and C+ (#3 on the upgrade list, with only one F left) for ATL to SJC. What surprises me is that Delta confirmed my F and C+ upgrades on these legs more than TWO WEEKS ago. I booked the fare back in December.

Not at all complaining -- at Silver, I didn't honestly expect a lot of upgrades. Hell, at 50k I almost never got anything on United.

Just curious...is this the norm for people?

And confirming F upgrades so far out for someone only Silver, is that normally how Delta rolls or did I luck out on this one?