Anyone who has understood signal analysis knows there is a phenomenon called "transient noise". Polls are subject to this effect. I would advise that we give some time for the dust to settle, after the immediate effects of the convention, etc. die out, and then concern ourselves with the polls. And then, only as we draw near the election date - October is probably the best month to begin to take the numbers more seriously.
The volatility of the polls is an intrinsic characteristic of uncertainty, and the higher it is, the less certain the numbers.
Do not, I repeat, do not confound this with the MoE. MoE is a statistical measure of error built into the survey itself. Volatility is an organic quality of the resulting numbers. You can manipulate the MoE. The volatility is almost impossible to manipulate. It is far more relevant to understanding the results of the polls than is the MoE.
At the moment, because of the transient noise, the volatility is very high. This makes the results very uncertain.
So beware of numbers that are changing willy nilly on a daily basis.
And yes, 538 is still the most reliable source for an impartial reading of the numbers.
