We've seen that River had a note in her diary of the date and place and event, so why when she was at the beach did she not know what was coming? There seems to be some playing around with her memories so her not actually remembering is explainable, but it was written there in in the diary which she had with her and consulted, as always, in TIA. Unless the page was torn out of course.
Or have I missed something?

Except the River in the spacesuit (assuming she's going to be in it at Lake Silencio) is younger River and older River clearly had no idea what was going when she was invited there. So is she the same person with memory loss for whatever reason or is she from say another timeline altogether?

That's exactly what I'm swinging towards. It was the young River just qualified who had it written in her diary so, providing the page hadn't been removed by someone else, it would be there in the older River's diary... if it's the same River. And River seems to know what's in her diary. Which adds weight to the idea of different Rivers from different timelines.

I'm not sure River didn't at least have some idea what was going to happen? At the end she said "of course".

She usually seems to know what is going to happen. She certainly knew all about the baby Melody and her kidnap.

And she's been in prison for the killing of The Doctor, so she's probably aware of the evidence against her.

older River does know who the astronaut is. And I imagine that she did know what was coming, all along. She still thought it was pretty cold. that's why she slapped him.

I think, possibly, she kills the Doctor, has her memory interfered with again, and then wouldn't recognise the significance of the words in the diary. She knows she's in prison for killing the Doctor, and knows that part of that plan was that she can never remember it. When the astronaut gets away she says 'of course' because she knows that she couldn't kill her younger self, it just isn't possible - i.e. it's only at that point she realises it's her younger self who in the suit and this was how she killed him.

Either that or some time rewritten stuff that we could spend months guessing at and still not get right (most likely!)

I've just rewatched the beginning of TIA, because I have a memory like a sieve. It does now look like River shooting at the spacesuit knows what's going on

"Of course not" - referencing the Einstein Grandfather Paradox thing. She can't kill herself???

River from TBB apologise to the Doctor, when she says he's gonna find out all about her. I'm guessiing at some point she knows how everything joins up

Though I'm still confused as to why Professor Song thinks 10 would know who she is. I'm guessing she knows what happens to 11 from FaS onwards, she must whether 11 is really dead or not (ok I know he's not likely to be 'really dead' but storywise he is at this point)

I don't have TIA to hand to watch again unfortunately, I'm stretching in the dark a bit without it, but as I recall she only appears to twig when she goes to shoot. She seems to check her diary at/before meetings, so you'd think, if she didn't remember, she would've checked when she got the invitation and know something significant is going to happen at that very specific place on that date and be more wary.
The note in the diary says the date, place, time but not what. And the foot of the opposite page says Utah (underlined) and space---- something her hand is over. Spacesuit I'm assuming. Now it doesn't mention his death, but it's early in the diary - you would think there would be things after it relating to it.

So either; the related info has been removed from the diary and her memory.
Or, she knows when she meets the others what's going to happen and has to let it play out. In which case she's an even harder case than I thought.
Or, the diary is different because this River is on a different timeline. Her crime is a different one or in a different time. But then that doesn't explain the 'of course not'.

Nope, no answers here!

And yes, in the library she doesn't seem to know at first look whether 10 is before or after 'her' Doctor. If she knew 11 was dead she would know he had to be before because she'd (supposedly) killed him sometime prior to that.
She must've seen next week's episode.

I do wonder though, why exactly did River go to the Library in the first place, was it to find the Doctor and continue her adventures with him, or was it simply to try and kill him?

Ofcourse River didn't have any choice, she had to save the tenth Doctor or she would never have been born. So even if she had gone there to kill him, she would have realised that Doc 10 was too early in the Doctors time stream to kill.

It would be quite ironic for a woman set on the idea of murder to be forced to sacrifice her own life to save her intended victim.

Don't get sucked into that episode too much, remember Moffat wrote it probably coming up to four years ago now, I highly doubt anything in there is going to be relevant to the finale! (Unless he planned that far ahead, which I wouldn't put past him at all)

I agree that Moff didn't plan this far in advance, however being the nice chappy that he is I reckon he will try to tie up the storylines so that Professor River Song's line aren't contridicted

then again maybe he won't