Accumulation stages only happens when less people know about it?
Accumulation stages, by definition, accumulation spikes happen when more people know about and are interested in the investment.
So the question is will there be another accumulation stage soon or is it impossible to have this stage as lots of people already know about bitcoin today?
I believe we'll see growth spur again in Q4 of 2018. On Wall Street there is a saying "sell in May and go away" which speaks to the lull in investment activity over the summer months in the Northern Hemisphere. People are vacationing, etc., and not doing as much investment business. When September comes around (the close of Summer) people get back into the business of investing and the markets usually see some gains.
I believe we'll see the same with Bitcoin.
I personally differ from your definition of what accumulation stage is.
I think that what is meant by OP by "accumulation stage" is a period of time where bitcoin prices are underappreciated and undervalued, and as a result, should be a good time to accumulate at lower prices despite markets being sluggish.
Whilst I agree that Q4 is going to be pretty interesting, as that would probably be the start of a major market recovery for bitcoin, that's not the best time to accumulate. Anything near the $6.6k bottom or below, probably is.