I've interpreted the Cyrenaic position to be "always pleasure in the moment" grab it now. Whereas Epicurus's philosophy was to make choices that would provide sustainable pleasure and the prospect that it would persist.
I agree (at least largely) with that statement of the Cyreniac position, but I don't think I would say the second sentence is accurate. Yes clearly "sustainability" (meaning the time element) is a factor to consider, but there's definitely no way to say flatly across the board that time is ALWAYS the deciding factor or even the MOST IMPORTANT factor. That's clear from the letter to Menoeceus:
"And just as with food he does not seek simply the larger share and nothing else, but rather the most pleasant, so he seeks to enjoy not the longest period of time, but the most pleasant."
So how does one rank the "most pleasant"? I think the first and most important aspect of the answer to that is that there's no universal single answer. The "most pleasant" by nature (by the Epicurean physics and understanding of the cosmos) is up to the individual given his or her own tastes and circumstances and preferences. Certainly I would think most people are going to consider the time element, but what about the person who wants to say "damn the torpedoes full speed ahead" and wants to climb to the top of a mountain to be there to see for a moment, even if he knows he'll never make it back down. Can such a person be said to be "wrong"? By what standard? I think Epicurus would say that that's between you and Nature to decide, with you making the call under all your individual circumstances.