So some people buy shares for £3.50 each

Hypothetically, in time, these shares rise to £10 each

The advisors tell people to sell now before the price drops.

Seems logical, but who do they sell them to, who would want them at that price, when the same advisors are telling people not to buy them yet, but wait until the price drops.

Or am I missing something, and it is not as simple as that