Quite interesting - Mayan day/nights and earth periods

[Spectrum]

Well lets see, Ra corrected the answers after any mistake...

When Ra told Don that they have difficulty with numbers, they also told him that he should requestion about any previous parts in the material where numbers occur. We don't know if Don did that. It's true that they sometimes corrected themselves while they talked in certain places, but nonetheless, numbers remain a bit of a sticky subject with Ra.

That quote you mention is precisely the only quote that could be interpreted as a so called "gradual" approach.

Not the only one, there are many areas in the Ra material that supports the gradual transition. Here Don questions about the transition from 2nd to 3rd density on Earth:

Questioner: Over how long a period of time was this transfiguration? It must have been very short.
Ra: I am Ra. The assumption is correct, in our terms at least—within a generation and one-half, as you know these things. Those who had been harvested of this planet were able to use the newly created physical complex of chemical elements suitable for third-density lessons.

Questioner: How long was the time of transition from second to third density? A generation and a half I believe you said. Is that correct?
Ra: I am Ra. This is correct, the time measured in your years being approximately 1,350.

Which is kind of congruent with the gradual 100 - 700 year transition.

Also Ra says time of the harvest ---note word harvest---is 2011.

That is true, but we know that 'harvest' and 'transition' from 3rd to 4th density are tied. I assure you I am not looking at this in an absolutist way, I just lean more towards gradual, and I am just including things in the Ra material that supports something more gradual, as opposed to sudden, to make this a more rounded discussion. When Ra says the time of harvest is 2011, it might start in 2011, and still be gradual. When people die, instead of doing the normal in-between incarnation things, they are going through the harvest process instead, from that date onwards (till completion).

Egyptians "Sun worshipers" Mayans "Sun worshipers"

Similarities between the Egyptians and 'those of South America' exist because Ra split their own social memory complex in two, one working with the Egyptians, and the other working with "those of South America" at the same time. Those who worked with the South Americans went back one more time to the South Americans, when Ra never returned (in the flesh - that is). We don't know if it were the Mayans.

are data not to be dismissed so lightly

Third party sources only muddy the waters, especially if one uses it to justify a theory, and the other considers it a questionable source.