Trying to clear the air for a few!!!

I noticed a few blogs on the topic of "since theyre in the past now and this is happening, why don't they recognize each other in the 2004 time" It's simple... sort of. They are affecting the past which will alter the present. This has not happened before. They are going back and changing stuff. now if the past plays out with the things they have done now, then in the future of the time frame they have affected they will recognize each other but they are not doing something that has always happened they are changing stuff..... thats what i think. And all would seem to agree with me... EXCEPT.... when sun discovered the photo of the O6, from the 70's. The only other way I can explain it is. The 2000's them are together in the 70's so therefore it is present them. They don't have memories of it because they have not done it yet. Therefore they in a sense havent done it yet.... make sense???